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MySQL Connector/J

   Copyright (c) 1997-2008 MySQL AB, 2009 Sun Microsystems, Inc. All
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   Abstract

   This manual describes MySQL Connector/J, the JDBC implementation
   for communicating with MySQL servers.

   Document generated on: 2009-09-11 (revision: 16574)
     _______________________________________________________

MySQL Connector/J

   MySQL provides connectivity for client applications developed in
   the Java programming language via a JDBC driver, which is called
   MySQL Connector/J.

   MySQL Connector/J is a JDBC Type 4 driver. Different versions are
   available that are compatible with the JDBC 3.0 and JDBC 4.0
   specifications. The Type 4 designation means that the driver is
   pure-Java implementation of the MySQL protocol and does not rely
   on the MySQL client libraries.

   Although JDBC is useful by itself, we would hope that if you are
   not familiar with JDBC that after reading the first few sections
   of this manual, that you would avoid using naked JDBC for all but
   the most trivial problems and consider using one of the popular
   persistence frameworks such as Hibernate
   (http://www.hibernate.org/), Spring's JDBC templates
   (http://www.springframework.org/) or Ibatis SQL Maps
   (http://ibatis.apache.org/) to do the majority of repetitive work
   and heavier lifting that is sometimes required with JDBC.

   This section is not designed to be a complete JDBC tutorial. If
   you need more information about using JDBC you might be interested
   in the following online tutorials that are more in-depth than the
   information presented here:

     * JDBC Basics
       (http://java.sun.com/docs/books/tutorial/jdbc/basics/index.htm
       l) --- A tutorial from Sun covering beginner topics in JDBC

     * JDBC Short Course
       (http://java.sun.com/developer/onlineTraining/Database/JDBCSho
       rtCourse/index.html) --- A more in-depth tutorial from Sun and
       JGuru

   Key topics:

     * For help with connection strings, connection options setting
       up your connection through JDBC, see Section 4.1,
       "Driver/Datasource Class Names, URL Syntax and Configuration
       Properties for Connector/J."

     * For tips on using Connector/J and JDBC with generic J2EE
       toolkits, see Section 5.2, "Using Connector/J with J2EE and
       Other Java Frameworks."

     * Developers using the Tomcat server platform, see Section
       5.2.2, "Using Connector/J with Tomcat."

     * Developers using JBoss, see Section 5.2.3, "Using Connector/J
       with JBoss."

     * Developers using Spring, see Section 5.2.4, "Using Connector/J
       with Spring."

   MySQL Enterprise MySQL Enterprise subscribers will find more
   information about using JDBC with MySQL in the Knowledge Base
   articles about JDBC
   (https://kb.mysql.com/search.php?cat=search&category=10). Access
   to the MySQL Knowledge Base collection of articles is one of the
   advantages of subscribing to MySQL Enterprise. For more
   information, see
   http://www.mysql.com/products/enterprise/advisors.html.

Chapter 1. Connector/J Versions

   There are currently four versions of MySQL Connector/J available:

     * Connector/J 5.1 is the Type 4 pure Java JDBC driver, which
       conforms to the JDBC 3.0 and JDBC 4.0 specifications. It
       provides compatibility with all the functionality of MySQL,
       including 4.1, 5.0, 5.1, and 5.4. Connector/J 5.1 provides
       ease of development features, including auto-registration with
       the Driver Manager, standardized validity checks, categorized
       SQLExceptions, support for the JDBC-4.0 XML processing, per
       connection client information, NCHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html), NVARCHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html) and NCLOB
       types. This release also includes all bug fixes up to and
       including Connector/J 5.0.6.

     * Connector/J 5.0 provides support for all the functionality
       offered by Connector/J 3.1 and includes distributed
       transaction (XA) support.

     * Connector/J 3.1 was designed for connectivity to MySQL 4.1 and
       MySQL 5.0 servers and provides support for all the
       functionality in MySQL 5.0 except distributed transaction (XA)
       support.

     * Connector/J 3.0 provides core functionality and was designed
       with connectivity to MySQL 3.x or MySQL 4.1 servers, although
       it will provide basic compatibility with later versions of
       MySQL. Connector/J 3.0 does not support server-side prepared
       statements, and does not support any of the features in
       versions of MySQL later than 4.1.

   The following table summarizes the Connector/J versions available:

   Connector/J version Driver Type JDBC version MySQL Server version
   Status
   5.1 4 3.0, 4.0 4.1, 5.0, 5.1, 5.4 Recommended version
   5.0 4 3.0 4.1, 5.0 Released version
   3.1 4 3.0 4.1, 5.0 Obsolete
   3.0 4 3.0 3.x, 4.1 Obsolete

   The current recommended version for Connector/J is 5.1. This guide
   covers all four connector versions, with specific notes given
   where a setting applies to a specific option.

1.1. Java Versions Supported

   The following table summarizes Connector/J Java dependencies:

   Connector/J version Java RTE required JDK required (to build
   source code)
   5.1 1.4.x, 1.5.x, 1.6.x 1.6.x and 1.5.x (or older)
   5.0 1.3.x, 1.4.x, 1.5.x, 1.6.x 1.4.2, 1.5.x, 1.6.x
   3.1 1.2.x, 1.3.x, 1.4.x, 1.5.x, 1.6.x 1.4.2, 1.5.x, 1.6.x
   3.0 1.2.x, 1.3.x, 1.4.x, 1.5.x, 1.6.x 1.4.2, 1.5.x, 1.6.x

   MySQL Connector/J does not support JDK-1.1.x or JDK-1.0.x.

   Because of the implementation of java.sql.Savepoint, Connector/J
   3.1.0 and newer will not run on a Java runtime older than 1.4
   unless the class verifier is turned off (by setting the
   -Xverify:none option to the Java runtime). This is because the
   class verifier will try to load the class definition for
   java.sql.Savepoint even though it is not accessed by the driver
   unless you actually use savepoint functionality.

   Caching functionality provided by Connector/J 3.1.0 or newer is
   also not available on JVMs older than 1.4.x, as it relies on
   java.util.LinkedHashMap which was first available in JDK-1.4.0.

   If you are building Connector/J from source code using the source
   distribution (see Section 2.4, "Installing from the Development
   Source Tree") then you must use JDK 1.4.2 or newer to compile the
   Connector package. For Connector/J 5.1 you must have both
   JDK-1.6.x. and JDK-1.5.x installed in order to be able to build
   the source code.

Chapter 2. Connector/J Installation

   You can install the Connector/J package using either the binary or
   source distribution. The binary distribution provides the easiest
   method for installation; the source distribution enables you to
   customize your installation further. With either solution, you
   must manually add the Connector/J location to your Java CLASSPATH.

   If you are upgrading from a previous version, read the upgrade
   information before continuing. See Section 2.3, "Upgrading from an
   Older Version."

2.1. Installing Connector/J from a Binary Distribution

   The easiest method of installation is to use the binary
   distribution of the Connector/J package. The binary distribution
   is available either as a Tar/Gzip or Zip file which you must
   extract to a suitable location and then optionally make the
   information about the package available by changing your CLASSPATH
   (see Section 2.2, "Installing the Driver and Configuring the
   CLASSPATH").

   MySQL Connector/J is distributed as a .zip or .tar.gz archive
   containing the sources, the class files, and the JAR archive named
   mysql-connector-java-[version]-bin.jar, and starting with
   Connector/J 3.1.8 a debug build of the driver in a file named
   mysql-connector-java-[version]-bin-g.jar.

   Starting with Connector/J 3.1.9, the .class files that constitute
   the JAR files are only included as part of the driver JAR file.

   You should not use the debug build of the driver unless instructed
   to do so when reporting a problem or a bug, as it is not designed
   to be run in production environments, and will have adverse
   performance impact when used. The debug binary also depends on the
   Aspect/J runtime library, which is located in the
   src/lib/aspectjrt.jar file that comes with the Connector/J
   distribution.

   You will need to use the appropriate graphical or command-line
   utility to extract the distribution (for example, WinZip for the
   .zip archive, and tar for the .tar.gz archive). Because there are
   potentially long file names in the distribution, we use the GNU
   tar archive format. You will need to use GNU tar (or an
   application that understands the GNU tar archive format) to unpack
   the .tar.gz variant of the distribution.

2.2. Installing the Driver and Configuring the CLASSPATH

   Once you have extracted the distribution archive, you can install
   the driver by placing mysql-connector-java-[version]-bin.jar in
   your classpath, either by adding the full path to it to your
   CLASSPATH environment variable, or by directly specifying it with
   the command line switch -cp when starting your JVM.

   If you are going to use the driver with the JDBC DriverManager,
   you would use com.mysql.jdbc.Driver as the class that implements
   java.sql.Driver.

   You can set the CLASSPATH environment variable under UNIX, Linux
   or Mac OS X either locally for a user within their .profile,
   .login or other login file. You can also set it globally by
   editing the global /etc/profile file.

   For example, under a C shell (csh, tcsh) you would add the
   Connector/J driver to your CLASSPATH using the following:
shell> setenv CLASSPATH /path/mysql-connector-java-[ver]-bin.jar:$CLA
SSPATH

   Or with a Bourne-compatible shell (sh, ksh, bash):
shell> export set CLASSPATH=/path/mysql-connector-java-[ver]-bin.jar:
$CLASSPATH

   Within Windows 2000, Windows XP, Windows Server 2003 and Windows
   Vista, you must set the environment variable through the System
   Control Panel.

   If you want to use MySQL Connector/J with an application server
   such as GlassFish, Tomcat or JBoss, you will have to read your
   vendor's documentation for more information on how to configure
   third-party class libraries, as most application servers ignore
   the CLASSPATH environment variable. For configuration examples for
   some J2EE application servers, see Section 5.2, "Using Connector/J
   with J2EE and Other Java Frameworks." However, the authoritative
   source for JDBC connection pool configuration information for your
   particular application server is the documentation for that
   application server.

   If you are developing servlets or JSPs, and your application
   server is J2EE-compliant, you can put the driver's .jar file in
   the WEB-INF/lib subdirectory of your webapp, as this is a standard
   location for third party class libraries in J2EE web applications.

   You can also use the MysqlDataSource or
   MysqlConnectionPoolDataSource classes in the
   com.mysql.jdbc.jdbc2.optional package, if your J2EE application
   server supports or requires them. Starting with Connector/J 5.0.0,
   the javax.sql.XADataSource interface is implemented via the
   com.mysql.jdbc.jdbc2.optional.MysqlXADataSource class, which
   supports XA distributed transactions when used in combination with
   MySQL server version 5.0.

   The various MysqlDataSource classes support the following
   parameters (through standard set mutators):

     * user

     * password

     * serverName (see the previous section about fail-over hosts)

     * databaseName

     * port

2.3. Upgrading from an Older Version

   We try to keep the upgrade process as easy as possible, however as
   is the case with any software, sometimes changes need to be made
   in new versions to support new features, improve existing
   functionality, or comply with new standards.

   This section has information about what users who are upgrading
   from one version of Connector/J to another (or to a new version of
   the MySQL server, with respect to JDBC functionality) should be
   aware of.

2.3.1. Upgrading from MySQL Connector/J 3.0 to 3.1

   Connector/J 3.1 is designed to be backward-compatible with
   Connector/J 3.0 as much as possible. Major changes are isolated to
   new functionality exposed in MySQL-4.1 and newer, which includes
   Unicode character sets, server-side prepared statements, SQLState
   codes returned in error messages by the server and various
   performance enhancements that can be enabled or disabled via
   configuration properties.

     * Unicode Character Sets --- See the next section, as well as
       Character Set Support
       (http://dev.mysql.com/doc/refman/5.0/en/charset.html), for
       information on this new feature of MySQL. If you have
       something misconfigured, it will usually show up as an error
       with a message similar to Illegal mix of collations.

     * Server-side Prepared Statements --- Connector/J 3.1 will
       automatically detect and use server-side prepared statements
       when they are available (MySQL server version 4.1.0 and
       newer).
       Starting with version 3.1.7, the driver scans SQL you are
       preparing via all variants of Connection.prepareStatement() to
       determine if it is a supported type of statement to prepare on
       the server side, and if it is not supported by the server, it
       instead prepares it as a client-side emulated prepared
       statement. You can disable this feature by passing
       emulateUnsupportedPstmts=false in your JDBC URL.
       If your application encounters issues with server-side
       prepared statements, you can revert to the older client-side
       emulated prepared statement code that is still presently used
       for MySQL servers older than 4.1.0 with the connection
       property useServerPrepStmts=false

     * Datetimes with all-zero components (0000-00-00 ...) --- These
       values can not be represented reliably in Java. Connector/J
       3.0.x always converted them to NULL when being read from a
       ResultSet.
       Connector/J 3.1 throws an exception by default when these
       values are encountered as this is the most correct behavior
       according to the JDBC and SQL standards. This behavior can be
       modified using the zeroDateTimeBehavior configuration
       property. The allowable values are:

          + exception (the default), which throws an SQLException
            with an SQLState of S1009.

          + convertToNull, which returns NULL instead of the date.

          + round, which rounds the date to the nearest closest value
            which is 0001-01-01.
       Starting with Connector/J 3.1.7, ResultSet.getString() can be
       decoupled from this behavior via noDatetimeStringSync=true
       (the default value is false) so that you can retrieve the
       unaltered all-zero value as a String. It should be noted that
       this also precludes using any time zone conversions, therefore
       the driver will not allow you to enable noDatetimeStringSync
       and useTimezone at the same time.

     * New SQLState Codes --- Connector/J 3.1 uses SQL:1999 SQLState
       codes returned by the MySQL server (if supported), which are
       different from the legacy X/Open state codes that Connector/J
       3.0 uses. If connected to a MySQL server older than
       MySQL-4.1.0 (the oldest version to return SQLStates as part of
       the error code), the driver will use a built-in mapping. You
       can revert to the old mapping by using the configuration
       property useSqlStateCodes=false.

     * ResultSet.getString() --- Calling ResultSet.getString() on a
       BLOB (http://dev.mysql.com/doc/refman/5.0/en/blob.html) column
       will now return the address of the byte[] array that
       represents it, instead of a String representation of the BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html). BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) values have
       no character set, so they cannot be converted to
       java.lang.Strings without data loss or corruption.
       To store strings in MySQL with LOB behavior, use one of the
       TEXT (http://dev.mysql.com/doc/refman/5.0/en/blob.html) types,
       which the driver will treat as a java.sql.Clob.

     * Debug builds --- Starting with Connector/J 3.1.8 a debug build
       of the driver in a file named
       mysql-connector-java-[version]-bin-g.jar is shipped alongside
       the normal binary jar file that is named
       mysql-connector-java-[version]-bin.jar.
       Starting with Connector/J 3.1.9, we do not ship the .class
       files unbundled, they are only available in the JAR archives
       that ship with the driver.
       You should not use the debug build of the driver unless
       instructed to do so when reporting a problem or bug, as it is
       not designed to be run in production environments, and will
       have adverse performance impact when used. The debug binary
       also depends on the Aspect/J runtime library, which is located
       in the src/lib/aspectjrt.jar file that comes with the
       Connector/J distribution.

2.3.2. Upgrading to MySQL Connector/J 5.1.x


     * In Connector/J 5.0.x and earlier, the alias for a table in a
       SELECT (http://dev.mysql.com/doc/refman/5.0/en/select.html)
       statement is returned when accessing the result set metadata
       using ResultSetMetaData.getColumnName(). This behavior however
       is not JDBC compliant, and in Connector/J 5.1 this behavior
       was changed so that the original table name, rather than the
       alias, is returned.
       The JDBC-compliant behavior is designed to let API users
       reconstruct the DML statement based on the metadata within
       ResultSet and ResultSetMetaData.
       You can get the alias for a column in a result set by calling
       ResultSetMetaData.getColumnLabel(). If you want to use the old
       noncompliant behavior with ResultSetMetaData.getColumnName(),
       use the useOldAliasMetadataBehavior option and set the value
       to true.
       In Connector/J 5.0.x the default value of
       useOldAliasMetadataBehavior was true, but in Connector/J 5.1
       this was changed to a default value of false.

2.3.3. JDBC-Specific Issues When Upgrading to MySQL Server 4.1 or
Newer


     * Using the UTF-8 Character Encoding - Prior to MySQL server
       version 4.1, the UTF-8 character encoding was not supported by
       the server, however the JDBC driver could use it, allowing
       storage of multiple character sets in latin1 tables on the
       server.
       Starting with MySQL-4.1, this functionality is deprecated. If
       you have applications that rely on this functionality, and can
       not upgrade them to use the official Unicode character support
       in MySQL server version 4.1 or newer, you should add the
       following property to your connection URL:
       useOldUTF8Behavior=true

     * Server-side Prepared Statements - Connector/J 3.1 will
       automatically detect and use server-side prepared statements
       when they are available (MySQL server version 4.1.0 and
       newer). If your application encounters issues with server-side
       prepared statements, you can revert to the older client-side
       emulated prepared statement code that is still presently used
       for MySQL servers older than 4.1.0 with the following
       connection property:
       useServerPrepStmts=false

2.4. Installing from the Development Source Tree

Caution

   You should read this section only if you are interested in helping
   us test our new code. If you just want to get MySQL Connector/J up
   and running on your system, you should use a standard binary
   release distribution.

   To install MySQL Connector/J from the development source tree,
   make sure that you have the following prerequisites:

     * A Bazaar client, to check out the sources from our Launchpad
       repository (available from http://bazaar-vcs.org/).

     * Apache Ant version 1.7 or newer (available from
       http://ant.apache.org/).

     * JDK 1.4.2 or later. Although MySQL Connector/J can be be used
       with older JDKs, to compile it from source you must have at
       least JDK 1.4.2. If you are building Connector/J 5.1 you will
       need JDK 1.6.x and an older JDK such as JDK 1.5.x. You will
       then need to point your JAVA_HOME environment variable at the
       older installation.

   The source code repository for MySQL Connector/J is located on
   Launchpad at https://code.launchpad.net/connectorj.

   To check out and compile a specific branch of MySQL Connector/J,
   follow these steps:

    1. Check out the latest code from the branch that you want with
       one of the following commands.
       To check out the latest development branch use:
shell> bzr branch lp:connectorj
       This creates a connectorj subdirectory in the current
       directory that contains the latest sources for the requested
       branch.
       To check out the latest 5.1 code use:
shell> bzr branch lp:connectorj/5.1
       This will create a 5.1 subdirectory in the current directory
       containing the latest 5.1 code.

    2. If you are building Connector/J 5.1 make sure that you have
       both JDK 1.6.x installed and an older JDK such as JDK 1.5.x.
       This is because Connector/J supports both JDBC 3.0 (which was
       prior to JDK 1.6.x) and JDBC 4.0. Set your JAVA_HOME
       environment variable to the path of the older JDK
       installation.

    3. Change location to either the connectorj or 5.1 directory,
       depending on which branch you want to build, to make it your
       current working directory. For example:
shell> cd connectorj

    4. If you are building Connector/J 5.1 you need to edit the
       build.xml to reflect the location of your JDK 1.6.x
       installation. The lines that you need to change are:
            <property name="com.mysql.jdbc.java6.javac" value="C:\jvm
s\jdk1.6.0\bin\javac.exe" />
            <property name="com.mysql.jdbc.java6.rtjar" value="C:\jvm
s\jdk1.6.0\jre\lib\rt.jar" />

       Alternatively, you can set the value of these property names
       through the Ant -D option.

    5. Issue the following command to compile the driver and create a
       .jar file suitable for installation:
shell> ant dist
       This creates a build directory in the current directory, where
       all build output will go. A directory is created in the build
       directory that includes the version number of the sources you
       are building from. This directory contains the sources,
       compiled .class files, and a .jar file suitable for
       deployment. For other possible targets, including ones that
       will create a fully packaged distribution, issue the following
       command:
shell> ant -projecthelp

    6. A newly created .jar file containing the JDBC driver will be
       placed in the directory build/mysql-connector-java-[version].
       Install the newly created JDBC driver as you would a binary
       .jar file that you download from MySQL by following the
       instructions in Section 2.2, "Installing the Driver and
       Configuring the CLASSPATH."

   A package containing both the binary and source code for
   Connector/J 5.1 can also be found at the following location:
   Connector/J 5.1 Download
   (http://dev.mysql.com/downloads/connector/j/5.1.html)

Chapter 3. Connector/J Examples

   Examples of using Connector/J are located throughout this
   document, this section provides a summary and links to these
   examples.

     * Example 5.1.1, "Connector/J: Obtaining a connection from the
       DriverManager"

     * Example 5.1.2, "Connector/J: Using java.sql.Statement to
       execute a SELECT query"

     * Example 5.1.3, "Connector/J: Calling Stored Procedures"

     * Example 5.1.3, "Connector/J: Using Connection.prepareCall()"

     * Example 5.1.3, "Connector/J: Registering output parameters"

     * Example 5.1.3, "Connector/J: Setting CallableStatement input
       parameters"

     * Example 5.1.3, "Connector/J: Retrieving results and output
       parameter values"

     * Example 5.1.4, "Connector/J: Retrieving AUTO_INCREMENT column
       values using Statement.getGeneratedKeys()"

     * Example 5.1.4, "Connector/J: Retrieving AUTO_INCREMENT column
       values using SELECT LAST_INSERT_ID()"

     * Example 5.1.4, "Connector/J: Retrieving AUTO_INCREMENT column
       values in Updatable ResultSets"

     * Example 5.2.1.1, "Connector/J: Using a connection pool with a
       J2EE application server"

     * Example 5.3, "Connector/J: Example of transaction with retry
       logic"

Chapter 4. Connector/J (JDBC) Reference

   This section of the manual contains reference material for MySQL
   Connector/J, some of which is automatically generated during the
   Connector/J build process.

4.1. Driver/Datasource Class Names, URL Syntax and Configuration
Properties for Connector/J

   The name of the class that implements java.sql.Driver in MySQL
   Connector/J is com.mysql.jdbc.Driver. The org.gjt.mm.mysql.Driver
   class name is also usable to remain backward-compatible with
   MM.MySQL. You should use this class name when registering the
   driver, or when otherwise configuring software to use MySQL
   Connector/J.

   The JDBC URL format for MySQL Connector/J is as follows, with
   items in square brackets ([, ]) being optional:
jdbc:mysql://[host][,failoverhost...][:port]/[database] ??
[?propertyName1][=propertyValue1][&propertyName2][=propertyValue2]...

   If the host name is not specified, it defaults to 127.0.0.1. If
   the port is not specified, it defaults to 3306, the default port
   number for MySQL servers.
jdbc:mysql://[host:port],[host:port].../[database] ??
[?propertyName1][=propertyValue1][&propertyName2][=propertyValue2]...

   If the database is not specified, the connection will be made with
   no default database. In this case, you will need to either call
   the setCatalog() method on the Connection instance or fully
   specify table names using the database name (that is, SELECT
   dbname.tablename.colname FROM dbname.tablename...) in your SQL.
   Not specifying the database to use upon connection is generally
   only useful when building tools that work with multiple databases,
   such as GUI database managers.

   MySQL Connector/J has fail-over support. This allows the driver to
   fail-over to any number of slave hosts and still perform read-only
   queries. Fail-over only happens when the connection is in an
   autoCommit(true) state, because fail-over can not happen reliably
   when a transaction is in progress. Most application servers and
   connection pools set autoCommit to true at the end of every
   transaction/connection use.

   The fail-over functionality has the following behavior:

     * If the URL property autoReconnect is false: Failover only
       happens at connection initialization, and failback occurs when
       the driver determines that the first host has become available
       again.

     * If the URL property autoReconnect is true: Failover happens
       when the driver determines that the connection has failed
       (before every query), and falls back to the first host when it
       determines that the host has become available again (after
       queriesBeforeRetryMaster queries have been issued).

   In either case, whenever you are connected to a "failed-over"
   server, the connection will be set to read-only state, so queries
   that would modify data will have exceptions thrown (the query will
   never be processed by the MySQL server).

   Configuration properties define how Connector/J will make a
   connection to a MySQL server. Unless otherwise noted, properties
   can be set for a DataSource object or for a Connection object.

   Configuration Properties can be set in one of the following ways:

     * Using the set*() methods on MySQL implementations of
       java.sql.DataSource (which is the preferred method when using
       implementations of java.sql.DataSource):

          + com.mysql.jdbc.jdbc2.optional.MysqlDataSource

          + com.mysql.jdbc.jdbc2.optional.MysqlConnectionPoolDataSour
            ce

     * As a key/value pair in the java.util.Properties instance
       passed to DriverManager.getConnection() or Driver.connect()

     * As a JDBC URL parameter in the URL given to
       java.sql.DriverManager.getConnection(),
       java.sql.Driver.connect() or the MySQL implementations of the
       javax.sql.DataSource setURL() method.

Note
       If the mechanism you use to configure a JDBC URL is XML-based,
       you will need to use the XML character literal &amp; to
       separate configuration parameters, as the ampersand is a
       reserved character for XML.

   The properties are listed in the following tables.

   Connection/Authentication. 
   Property Name Definition Default Value Since Version 
   user The user to connect as   all versions
   password The password to use when connecting   all versions
   socketFactory The name of the class that the driver should use for
   creating socket connections to the server. This class must
   implement the interface 'com.mysql.jdbc.SocketFactory' and have
   public no-args constructor. com.mysql.jdbc.StandardSocketFactory
   3.0.3
   connectTimeout Timeout for socket connect (in milliseconds), with
   0 being no timeout. Only works on JDK-1.4 or newer. Defaults to
   '0'. 0 3.0.1
   socketTimeout Timeout on network socket operations (0, the default
   means no timeout). 0 3.0.1
   connectionLifecycleInterceptors A comma-delimited list of classes
   that implement "com.mysql.jdbc.ConnectionLifecycleInterceptor"
   that should notified of connection lifecycle events (creation,
   destruction, commit, rollback, setCatalog and setAutoCommit) and
   potentially alter the execution of these commands.
   ConnectionLifecycleInterceptors are "stackable", more than one
   interceptor may be specified via the configuration property as a
   comma-delimited list, with the interceptors executed in order from
   left to right.   5.1.4
   useConfigs Load the comma-delimited list of configuration
   properties before parsing the URL or applying user-specified
   properties. These configurations are explained in the
   'Configurations' of the documentation.   3.1.5
   interactiveClient Set the CLIENT_INTERACTIVE flag, which tells
   MySQL to timeout connections based on INTERACTIVE_TIMEOUT instead
   of WAIT_TIMEOUT false 3.1.0
   localSocketAddress Hostname or IP address given to explicitly
   configure the interface that the driver will bind the client side
   of the TCP/IP connection to when connecting.   5.0.5
   propertiesTransform An implementation of
   com.mysql.jdbc.ConnectionPropertiesTransform that the driver will
   use to modify URL properties passed to the driver before
   attempting a connection   3.1.4
   useCompression Use zlib compression when communicating with the
   server (true/false)? Defaults to 'false'. false 3.0.17

   Networking. 
   Property Name Definition Default Value Since Version 
   maxAllowedPacket Maximum allowed packet size to send to server. If
   not set, the value of system variable 'max_allowed_packet' will be
   used to initialize this upon connecting. This value will not take
   effect if set larger than the value of 'max_allowed_packet'. -1
   5.1.8
   tcpKeepAlive If connecting using TCP/IP, should the driver set
   SO_KEEPALIVE? true 5.0.7
   tcpNoDelay If connecting using TCP/IP, should the driver set
   SO_TCP_NODELAY (disabling the Nagle Algorithm)? true 5.0.7
   tcpRcvBuf If connecting using TCP/IP, should the driver set
   SO_RCV_BUF to the given value? The default value of '0', means use
   the platform default value for this property) 0 5.0.7
   tcpSndBuf If connecting using TCP/IP, shuold the driver set
   SO_SND_BUF to the given value? The default value of '0', means use
   the platform default value for this property) 0 5.0.7
   tcpTrafficClass If connecting using TCP/IP, should the driver set
   traffic class or type-of-service fields ?See the documentation for
   java.net.Socket.setTrafficClass() for more information. 0 5.0.7

   High Availability and Clustering. 
   Property Name Definition Default Value Since Version 
   autoReconnect Should the driver try to re-establish stale and/or
   dead connections? If enabled the driver will throw an exception
   for a queries issued on a stale or dead connection, which belong
   to the current transaction, but will attempt reconnect before the
   next query issued on the connection in a new transaction. The use
   of this feature is not recommended, because it has side effects
   related to session state and data consistency when applications
   don't handle SQLExceptions properly, and is only designed to be
   used when you are unable to configure your application to handle
   SQLExceptions resulting from dead and stale connections properly.
   Alternatively, investigate setting the MySQL server variable
   "wait_timeout" to some high value rather than the default of 8
   hours. false 1.1
   autoReconnectForPools Use a reconnection strategy appropriate for
   connection pools (defaults to 'false') false 3.1.3
   failOverReadOnly When failing over in autoReconnect mode, should
   the connection be set to 'read-only'? true 3.0.12
   maxReconnects Maximum number of reconnects to attempt if
   autoReconnect is true, default is '3'. 3 1.1
   reconnectAtTxEnd If autoReconnect is set to true, should the
   driver attempt reconnections at the end of every transaction?
   false 3.0.10
   retriesAllDown When using loadbalancing, the number of times the
   driver should cycle through available hosts, attempting to
   connect. Between cycles, the driver will pause for 250ms if no
   servers are available. 120 5.1.6
   initialTimeout If autoReconnect is enabled, the initial time to
   wait between re-connect attempts (in seconds, defaults to '2'). 2
   1.1
   roundRobinLoadBalance When autoReconnect is enabled, and
   failoverReadonly is false, should we pick hosts to connect to on a
   round-robin basis? false 3.1.2
   queriesBeforeRetryMaster Number of queries to issue before falling
   back to master when failed over (when using multi-host failover).
   Whichever condition is met first, 'queriesBeforeRetryMaster' or
   'secondsBeforeRetryMaster' will cause an attempt to be made to
   reconnect to the master. Defaults to 50. 50 3.0.2
   secondsBeforeRetryMaster How long should the driver wait, when
   failed over, before attempting 30 3.0.2
   selfDestructOnPingMaxOperations =If set to a non-zero value, the
   driver will report close the connection and report failure when
   Connection.ping() or Connection.isValid(int) is called if the
   connnection's count of commands sent to the server exceeds this
   value. 0 5.1.6
   selfDestructOnPingSecondsLifetime If set to a non-zero value, the
   driver will report close the connection and report failure when
   Connection.ping() or Connection.isValid(int) is called if the
   connnection's lifetime exceeds this value. 0 5.1.6
   resourceId A globally unique name that identifies the resource
   that this datasource or connection is connected to, used for
   XAResource.isSameRM() when the driver can't determine this value
   based on hostnames used in the URL   5.0.1

   Security. 
   Property Name Definition Default Value Since Version 
   allowMultiQueries Allow the use of ';' to delimit multiple queries
   during one statement (true/false), defaults to 'false' false 3.1.1
   useSSL Use SSL when communicating with the server (true/false),
   defaults to 'false' false 3.0.2
   requireSSL Require SSL connection if useSSL=true? (defaults to
   'false'). false 3.1.0
   verifyServerCertificate If "useSSL" is set to "true", should the
   driver verify the server's certificate? When using this feature,
   the keystore parameters should be specified by the
   "clientCertificateKeyStore*" properties, rather than system
   properties. true 5.1.6
   clientCertificateKeyStoreUrl URL to the client certificate
   KeyStore (if not specified, use defaults)   5.1.0
   clientCertificateKeyStoreType KeyStore type for client
   certificates (NULL or empty means use default, standard keystore
   types supported by the JVM are "JKS" and "PKCS12", your
   environment may have more available depending on what security
   products are installed and available to the JVM.   5.1.0
   clientCertificateKeyStorePassword Password for the client
   certificates KeyStore   5.1.0
   trustCertificateKeyStoreUrl URL to the trusted root certificate
   KeyStore (if not specified, use defaults)   5.1.0
   trustCertificateKeyStoreType KeyStore type for trusted root
   certificates (NULL or empty means use default, standard keystore
   types supported by the JVM are "JKS" and "PKCS12", your
   environment may have more available depending on what security
   products are installed and available to the JVM.   5.1.0
   trustCertificateKeyStorePassword Password for the trusted root
   certificates KeyStore   5.1.0
   allowLoadLocalInfile Should the driver allow use of 'LOAD DATA
   LOCAL INFILE...' (defaults to 'true'). true 3.0.3
   allowUrlInLocalInfile Should the driver allow URLs in 'LOAD DATA
   LOCAL INFILE' statements? false 3.1.4
   paranoid Take measures to prevent exposure sensitive information
   in error messages and clear data structures holding sensitive data
   when possible? (defaults to 'false') false 3.0.1
   passwordCharacterEncoding What character encoding is used for
   passwords? Leaving this set to the default value (null), uses the
   platform character set, which works for ISO8859_1 (i.e. "latin1")
   passwords. For passwords in other character encodings, the
   encoding will have to be specified with this property, as it's not
   possible for the driver to auto-detect this.   5.1.7

   Performance Extensions. 
   Property Name Definition Default Value Since Version 
   callableStmtCacheSize If 'cacheCallableStmts' is enabled, how many
   callable statements should be cached? 100 3.1.2
   metadataCacheSize The number of queries to cache ResultSetMetadata
   for if cacheResultSetMetaData is set to 'true' (default 50) 50
   3.1.1
   useLocalSessionState Should the driver refer to the internal
   values of autocommit and transaction isolation that are set by
   Connection.setAutoCommit() and
   Connection.setTransactionIsolation() and transaction state as
   maintained by the protocol, rather than querying the database or
   blindly sending commands to the database for commit() or
   rollback() method calls? false 3.1.7
   useLocalTransactionState Should the driver use the in-transaction
   state provided by the MySQL protocol to determine if a commit() or
   rollback() should actually be sent to the database? false 5.1.7
   prepStmtCacheSize If prepared statement caching is enabled, how
   many prepared statements should be cached? 25 3.0.10
   prepStmtCacheSqlLimit If prepared statement caching is enabled,
   what's the largest SQL the driver will cache the parsing for? 256
   3.0.10
   alwaysSendSetIsolation Should the driver always communicate with
   the database when Connection.setTransactionIsolation() is called?
   If set to false, the driver will only communicate with the
   database when the requested transaction isolation is different
   than the whichever is newer, the last value that was set via
   Connection.setTransactionIsolation(), or the value that was read
   from the server when the connection was established. true 3.1.7
   maintainTimeStats Should the driver maintain various internal
   timers to enable idle time calculations as well as more verbose
   error messages when the connection to the server fails? Setting
   this property to false removes at least two calls to
   System.getCurrentTimeMillis() per query. true 3.1.9
   useCursorFetch If connected to MySQL > 5.0.2, and setFetchSize() >
   0 on a statement, should that statement use cursor-based fetching
   to retrieve rows? false 5.0.0
   blobSendChunkSize Chunk to use when sending BLOB/CLOBs via
   ServerPreparedStatements 1048576 3.1.9
   cacheCallableStmts Should the driver cache the parsing stage of
   CallableStatements false 3.1.2
   cachePrepStmts Should the driver cache the parsing stage of
   PreparedStatements of client-side prepared statements, the "check"
   for suitability of server-side prepared and server-side prepared
   statements themselves? false 3.0.10
   cacheResultSetMetadata Should the driver cache ResultSetMetaData
   for Statements and PreparedStatements? (Req. JDK-1.4+, true/false,
   default 'false') false 3.1.1
   cacheServerConfiguration Should the driver cache the results of
   'SHOW VARIABLES' and 'SHOW COLLATION' on a per-URL basis? false
   3.1.5
   defaultFetchSize The driver will call setFetchSize(n) with this
   value on all newly-created Statements 0 3.1.9
   dontTrackOpenResources The JDBC specification requires the driver
   to automatically track and close resources, however if your
   application doesn't do a good job of explicitly calling close() on
   statements or result sets, this can cause memory leakage. Setting
   this property to true relaxes this constraint, and can be more
   memory efficient for some applications. false 3.1.7
   dynamicCalendars Should the driver retrieve the default calendar
   when required, or cache it per connection/session? false 3.1.5
   elideSetAutoCommits If using MySQL-4.1 or newer, should the driver
   only issue 'set autocommit=n' queries when the server's state
   doesn't match the requested state by
   Connection.setAutoCommit(boolean)? false 3.1.3
   enableQueryTimeouts When enabled, query timeouts set via
   Statement.setQueryTimeout() use a shared java.util.Timer instance
   for scheduling. Even if the timeout doesn't expire before the
   query is processed, there will be memory used by the TimerTask for
   the given timeout which won't be reclaimed until the time the
   timeout would have expired if it hadn't been cancelled by the
   driver. High-load environments might want to consider disabling
   this functionality. true 5.0.6
   holdResultsOpenOverStatementClose Should the driver close result
   sets on Statement.close() as required by the JDBC specification?
   false 3.1.7
   largeRowSizeThreshold What size result set row should the JDBC
   driver consider "large", and thus use a more memory-efficient way
   of representing the row internally? 2048 5.1.1
   loadBalanceStrategy If using a load-balanced connection to connect
   to SQL nodes in a MySQL Cluster/NDB configuration (by using the
   URL prefix "jdbc:mysql:loadbalance://"), which load balancing
   algorithm should the driver use: (1) "random" - the driver will
   pick a random host for each request. This tends to work better
   than round-robin, as the randomness will somewhat account for
   spreading loads where requests vary in response time, while
   round-robin can sometimes lead to overloaded nodes if there are
   variations in response times across the workload. (2)
   "bestResponseTime" - the driver will route the request to the host
   that had the best response time for the previous transaction.
   random 5.0.6
   locatorFetchBufferSize If 'emulateLocators' is configured to
   'true', what size buffer should be used when fetching BLOB data
   for getBinaryInputStream? 1048576 3.2.1
   rewriteBatchedStatements Should the driver use multiqueries
   (irregardless of the setting of "allowMultiQueries") as well as
   rewriting of prepared statements for INSERT into multi-value
   inserts when executeBatch() is called? Notice that this has the
   potential for SQL injection if using plain java.sql.Statements and
   your code doesn't sanitize input correctly. Notice that for
   prepared statements, server-side prepared statements can not
   currently take advantage of this rewrite option, and that if you
   don't specify stream lengths when using
   PreparedStatement.set*Stream(), the driver won't be able to
   determine the optimum number of parameters per batch and you might
   receive an error from the driver that the resultant packet is too
   large. Statement.getGeneratedKeys() for these rewritten statements
   only works when the entire batch includes INSERT statements. false
   3.1.13
   useDirectRowUnpack Use newer result set row unpacking code that
   skips a copy from network buffers to a MySQL packet instance and
   instead reads directly into the result set row data buffers. true
   5.1.1
   useDynamicCharsetInfo Should the driver use a per-connection cache
   of character set information queried from the server when
   necessary, or use a built-in static mapping that is more
   efficient, but isn't aware of custom character sets or character
   sets implemented after the release of the JDBC driver? true 5.0.6
   useFastDateParsing Use internal String->Date/Time/Timestamp
   conversion routines to avoid excessive object creation? true 5.0.5
   useFastIntParsing Use internal String->Integer conversion routines
   to avoid excessive object creation? true 3.1.4
   useJvmCharsetConverters Always use the character encoding routines
   built into the JVM, rather than using lookup tables for
   single-byte character sets? false 5.0.1
   useReadAheadInput Use newer, optimized non-blocking, buffered
   input stream when reading from the server? true 3.1.5

   Debugging/Profiling. 
   Property Name Definition Default Value Since Version 
   logger The name of a class that implements
   "com.mysql.jdbc.log.Log" that will be used to log messages to.
   (default is "com.mysql.jdbc.log.StandardLogger", which logs to
   STDERR) com.mysql.jdbc.log.StandardLogger 3.1.1
   gatherPerfMetrics Should the driver gather performance metrics,
   and report them via the configured logger every
   'reportMetricsIntervalMillis' milliseconds? false 3.1.2
   profileSQL Trace queries and their execution/fetch times to the
   configured logger (true/false) defaults to 'false' false 3.1.0
   profileSql Deprecated, use 'profileSQL' instead. Trace queries and
   their execution/fetch times on STDERR (true/false) defaults to
   'false'   2.0.14
   reportMetricsIntervalMillis If 'gatherPerfMetrics' is enabled, how
   often should they be logged (in ms)? 30000 3.1.2
   maxQuerySizeToLog Controls the maximum length/size of a query that
   will get logged when profiling or tracing 2048 3.1.3
   packetDebugBufferSize The maximum number of packets to retain when
   'enablePacketDebug' is true 20 3.1.3
   slowQueryThresholdMillis If 'logSlowQueries' is enabled, how long
   should a query (in ms) before it is logged as 'slow'? 2000 3.1.2
   slowQueryThresholdNanos If 'useNanosForElapsedTime' is set to
   true, and this property is set to a non-zero value, the driver
   will use this threshold (in nanosecond units) to determine if a
   query was slow. 0 5.0.7
   useUsageAdvisor Should the driver issue 'usage' warnings advising
   proper and efficient usage of JDBC and MySQL Connector/J to the
   log (true/false, defaults to 'false')? false 3.1.1
   autoGenerateTestcaseScript Should the driver dump the SQL it is
   executing, including server-side prepared statements to STDERR?
   false 3.1.9
   autoSlowLog Instead of using slowQueryThreshold* to determine if a
   query is slow enough to be logged, maintain statistics that allow
   the driver to determine queries that are outside the 99th
   percentile? true 5.1.4
   clientInfoProvider The name of a class that implements the
   com.mysql.jdbc.JDBC4ClientInfoProvider interface in order to
   support JDBC-4.0's Connection.get/setClientInfo() methods
   com.mysql.jdbc.JDBC4CommentClientInfoProvider 5.1.0
   dumpMetadataOnColumnNotFound Should the driver dump the
   field-level metadata of a result set into the exception message
   when ResultSet.findColumn() fails? false 3.1.13
   dumpQueriesOnException Should the driver dump the contents of the
   query sent to the server in the message for SQLExceptions? false
   3.1.3
   enablePacketDebug When enabled, a ring-buffer of
   'packetDebugBufferSize' packets will be kept, and dumped when
   exceptions are thrown in key areas in the driver's code false
   3.1.3
   explainSlowQueries If 'logSlowQueries' is enabled, should the
   driver automatically issue an 'EXPLAIN' on the server and send the
   results to the configured log at a WARN level? false 3.1.2
   includeInnodbStatusInDeadlockExceptions Include the output of
   "SHOW ENGINE INNODB STATUS" in exception messages when deadlock
   exceptions are detected? false 5.0.7
   logSlowQueries Should queries that take longer than
   'slowQueryThresholdMillis' be logged? false 3.1.2
   logXaCommands Should the driver log XA commands sent by
   MysqlXaConnection to the server, at the DEBUG level of logging?
   false 5.0.5
   profilerEventHandler Name of a class that implements the interface
   com.mysql.jdbc.profiler.ProfilerEventHandler that will be used to
   handle profiling/tracing events.
   com.mysql.jdbc.profiler.LoggingProfilerEventHandler 5.1.6
   resultSetSizeThreshold If the usage advisor is enabled, how many
   rows should a result set contain before the driver warns that it
   is suspiciously large? 100 5.0.5
   traceProtocol Should trace-level network protocol be logged? false
   3.1.2
   useNanosForElapsedTime For profiling/debugging functionality that
   measures elapsed time, should the driver try to use nanoseconds
   resolution if available (JDK >= 1.5)? false 5.0.7

   Miscellaneous. 
   Property Name Definition Default Value Since Version 
   useUnicode Should the driver use Unicode character encodings when
   handling strings? Should only be used when the driver can't
   determine the character set mapping, or you are trying to 'force'
   the driver to use a character set that MySQL either doesn't
   natively support (such as UTF-8), true/false, defaults to 'true'
   true 1.1g
   characterEncoding If 'useUnicode' is set to true, what character
   encoding should the driver use when dealing with strings?
   (defaults is to 'autodetect')   1.1g
   characterSetResults Character set to tell the server to return
   results as.   3.0.13
   connectionCollation If set, tells the server to use this collation
   via 'set collation_connection'   3.0.13
   useBlobToStoreUTF8OutsideBMP Tells the driver to treat
   [MEDIUM/LONG]BLOB columns as [LONG]VARCHAR columns holding text
   encoded in UTF-8 that has characters outside the BMP (4-byte
   encodings), which MySQL server can't handle natively. false 5.1.3
   utf8OutsideBmpExcludedColumnNamePattern When
   "useBlobToStoreUTF8OutsideBMP" is set to "true", column names
   matching the given regex will still be treated as BLOBs unless
   they match the regex specified for
   "utf8OutsideBmpIncludedColumnNamePattern". The regex must follow
   the patterns used for the java.util.regex package.   5.1.3
   utf8OutsideBmpIncludedColumnNamePattern Used to specify exclusion
   rules to "utf8OutsideBmpExcludedColumnNamePattern". The regex must
   follow the patterns used for the java.util.regex package.   5.1.3
   sessionVariables A comma-separated list of name/value pairs to be
   sent as SET SESSION ... to the server when the driver connects.
   3.1.8
   useColumnNamesInFindColumn Prior to JDBC-4.0, the JDBC
   specification had a bug related to what could be given as a
   "column name" to ResultSet methods like findColumn(), or getters
   that took a String property. JDBC-4.0 clarified "column name" to
   mean the label, as given in an "AS" clause and returned by
   ResultSetMetaData.getColumnLabel(), and if no AS clause, the
   column name. Setting this property to "true" will give behavior
   that is congruent to JDBC-3.0 and earlier versions of the JDBC
   specification, but which because of the specification bug could
   give unexpected results. This property is preferred over
   "useOldAliasMetadataBehavior" unless you need the specific
   behavior that it provides with respect to ResultSetMetadata. false
   5.1.7
   allowNanAndInf Should the driver allow NaN or +/- INF values in
   PreparedStatement.setDouble()? false 3.1.5
   autoClosePStmtStreams Should the driver automatically call
   .close() on streams/readers passed as arguments via set*()
   methods? false 3.1.12
   autoDeserialize Should the driver automatically detect and
   de-serialize objects stored in BLOB fields? false 3.1.5
   blobsAreStrings Should the driver always treat BLOBs as Strings -
   specifically to work around dubious metadata returned by the
   server for GROUP BY clauses? false 5.0.8
   capitalizeTypeNames Capitalize type names in DatabaseMetaData?
   (usually only useful when using WebObjects, true/false, defaults
   to 'false') true 2.0.7
   clobCharacterEncoding The character encoding to use for sending
   and retrieving TEXT, MEDIUMTEXT and LONGTEXT values instead of the
   configured connection characterEncoding   5.0.0
   clobberStreamingResults This will cause a 'streaming' ResultSet to
   be automatically closed, and any outstanding data still streaming
   from the server to be discarded if another query is executed
   before all the data has been read from the server. false 3.0.9
   compensateOnDuplicateKeyUpdateCounts Should the driver compensate
   for the update counts of "ON DUPLICATE KEY" INSERT statements (2 =
   1, 0 = 1) when using prepared statements? false 5.1.7
   continueBatchOnError Should the driver continue processing batch
   commands if one statement fails. The JDBC spec allows either way
   (defaults to 'true'). true 3.0.3
   createDatabaseIfNotExist Creates the database given in the URL if
   it doesn't yet exist. Assumes the configured user has permissions
   to create databases. false 3.1.9
   emptyStringsConvertToZero Should the driver allow conversions from
   empty string fields to numeric values of '0'? true 3.1.8
   emulateLocators Should the driver emulate java.sql.Blobs with
   locators? With this feature enabled, the driver will delay loading
   the actual Blob data until the one of the retrieval methods
   (getInputStream(), getBytes(), and so forth) on the blob data
   stream has been accessed. For this to work, you must use a column
   alias with the value of the column to the actual name of the Blob.
   The feature also has the following restrictions: The SELECT that
   created the result set must reference only one table, the table
   must have a primary key; the SELECT must alias the original blob
   column name, specified as a string, to an alternate name; the
   SELECT must cover all columns that make up the primary key. false
   3.1.0
   emulateUnsupportedPstmts Should the driver detect prepared
   statements that are not supported by the server, and replace them
   with client-side emulated versions? true 3.1.7
   exceptionInterceptors Comma-delimited list of classes that
   implement com.mysql.jdbc.ExceptionInterceptor. These classes will
   be instantiated one per Connection instance, and all SQLExceptions
   thrown by the driver will be allowed to be intercepted by these
   interceptors, in a chained fashion, with the first class listed as
   the head of the chain.   5.1.8
   functionsNeverReturnBlobs Should the driver always treat data from
   functions returning BLOBs as Strings - specifically to work around
   dubious metadata returned by the server for GROUP BY clauses?
   false 5.0.8
   generateSimpleParameterMetadata Should the driver generate
   simplified parameter metadata for PreparedStatements when no
   metadata is available either because the server couldn't support
   preparing the statement, or server-side prepared statements are
   disabled? false 5.0.5
   ignoreNonTxTables Ignore non-transactional table warning for
   rollback? (defaults to 'false'). false 3.0.9
   jdbcCompliantTruncation Should the driver throw
   java.sql.DataTruncation exceptions when data is truncated as is
   required by the JDBC specification when connected to a server that
   supports warnings (MySQL 4.1.0 and newer)? This property has no
   effect if the server sql-mode includes STRICT_TRANS_TABLES. true
   3.1.2
   loadBalanceBlacklistTimeout Time in milliseconds between checks of
   servers which are unavailable. 0 5.1.0
   maxRows The maximum number of rows to return (0, the default means
   return all rows). -1 all versions
   netTimeoutForStreamingResults What value should the driver
   automatically set the server setting 'net_write_timeout' to when
   the streaming result sets feature is in use? (value has unit of
   seconds, the value '0' means the driver will not try and adjust
   this value) 600 5.1.0
   noAccessToProcedureBodies When determining procedure parameter
   types for CallableStatements, and the connected user can't access
   procedure bodies through "SHOW CREATE PROCEDURE" or select on
   mysql.proc should the driver instead create basic metadata (all
   parameters reported as IN VARCHARs, but allowing
   registerOutParameter() to be called on them anyway) instead of
   throwing an exception? false 5.0.3
   noDatetimeStringSync Don't ensure that
   ResultSet.getDatetimeType().toString().equals(ResultSet.getString(
   )) false 3.1.7
   noTimezoneConversionForTimeType Don't convert TIME values using
   the server timezone if 'useTimezone'='true' false 5.0.0
   nullCatalogMeansCurrent When DatabaseMetadataMethods ask for a
   'catalog' parameter, does the value null mean use the current
   catalog? (this is not JDBC-compliant, but follows legacy behavior
   from earlier versions of the driver) true 3.1.8
   nullNamePatternMatchesAll Should DatabaseMetaData methods that
   accept *pattern parameters treat null the same as '%' (this is not
   JDBC-compliant, however older versions of the driver accepted this
   departure from the specification) true 3.1.8
   overrideSupportsIntegrityEnhancementFacility Should the driver
   return "true" for
   DatabaseMetaData.supportsIntegrityEnhancementFacility() even if
   the database doesn't support it to workaround applications that
   require this method to return "true" to signal support of foreign
   keys, even though the SQL specification states that this facility
   contains much more than just foreign key support (one such
   application being OpenOffice)? false 3.1.12
   padCharsWithSpace If a result set column has the CHAR type and the
   value does not fill the amount of characters specified in the DDL
   for the column, should the driver pad the remaining characters
   with space (for ANSI compliance)? false 5.0.6
   pedantic Follow the JDBC spec to the letter. false 3.0.0
   pinGlobalTxToPhysicalConnection When using XAConnections, should
   the driver ensure that operations on a given XID are always routed
   to the same physical connection? This allows the XAConnection to
   support "XA START ... JOIN" after "XA END" has been called false
   5.0.1
   populateInsertRowWithDefaultValues When using ResultSets that are
   CONCUR_UPDATABLE, should the driver pre-populate the "insert" row
   with default values from the DDL for the table used in the query
   so those values are immediately available for ResultSet accessors?
   This functionality requires a call to the database for metadata
   each time a result set of this type is created. If disabled (the
   default), the default values will be populated by the an internal
   call to refreshRow() which pulls back default values and/or values
   changed by triggers. false 5.0.5
   processEscapeCodesForPrepStmts Should the driver process escape
   codes in queries that are prepared? true 3.1.12
   queryTimeoutKillsConnection If the timeout given in
   Statement.setQueryTimeout() expires, should the driver forcibly
   abort the Connection instead of attempting to abort the query?
   false 5.1.9
   relaxAutoCommit If the version of MySQL the driver connects to
   does not support transactions, still allow calls to commit(),
   rollback() and setAutoCommit() (true/false, defaults to 'false')?
   false 2.0.13
   retainStatementAfterResultSetClose Should the driver retain the
   Statement reference in a ResultSet after ResultSet.close() has
   been called. This is not JDBC-compliant after JDBC-4.0. false
   3.1.11
   rollbackOnPooledClose Should the driver issue a rollback() when
   the logical connection in a pool is closed? true 3.0.15
   runningCTS13 Enables workarounds for bugs in Sun's JDBC compliance
   testsuite version 1.3 false 3.1.7
   serverTimezone Override detection/mapping of timezone. Used when
   timezone from server doesn't map to Java timezone   3.0.2
   statementInterceptors A comma-delimited list of classes that
   implement "com.mysql.jdbc.StatementInterceptor" that should be
   placed "in between" query execution to influence the results.
   StatementInterceptors are "chainable", the results returned by the
   "current" interceptor will be passed on to the next in in the
   chain, from left-to-right order, as specified in this property.
   5.1.1
   strictFloatingPoint Used only in older versions of compliance test
   false 3.0.0
   strictUpdates Should the driver do strict checking (all primary
   keys selected) of updatable result sets (true, false, defaults to
   'true')? true 3.0.4
   tinyInt1isBit Should the driver treat the datatype TINYINT(1) as
   the BIT type (because the server silently converts BIT ->
   TINYINT(1) when creating tables)? true 3.0.16
   transformedBitIsBoolean If the driver converts TINYINT(1) to a
   different type, should it use BOOLEAN instead of BIT for future
   compatibility with MySQL-5.0, as MySQL-5.0 has a BIT type? false
   3.1.9
   treatUtilDateAsTimestamp Should the driver treat java.util.Date as
   a TIMESTAMP for the purposes of PreparedStatement.setObject()?
   true 5.0.5
   ultraDevHack Create PreparedStatements for prepareCall() when
   required, because UltraDev is broken and issues a prepareCall()
   for _all_ statements? (true/false, defaults to 'false') false
   2.0.3
   useAffectedRows Don't set the CLIENT_FOUND_ROWS flag when
   connecting to the server (not JDBC-compliant, will break most
   applications that rely on "found" rows vs. "affected rows" for DML
   statements), but does cause "correct" update counts from "INSERT
   ... ON DUPLICATE KEY UPDATE" statements to be returned by the
   server. false 5.1.7
   useGmtMillisForDatetimes Convert between session timezone and GMT
   before creating Date and Timestamp instances (value of "false" is
   legacy behavior, "true" leads to more JDBC-compliant behavior.
   false 3.1.12
   useHostsInPrivileges Add '@hostname' to users in
   DatabaseMetaData.getColumn/TablePrivileges() (true/false),
   defaults to 'true'. true 3.0.2
   useInformationSchema When connected to MySQL-5.0.7 or newer,
   should the driver use the INFORMATION_SCHEMA to derive information
   used by DatabaseMetaData? false 5.0.0
   useJDBCCompliantTimezoneShift Should the driver use JDBC-compliant
   rules when converting TIME/TIMESTAMP/DATETIME values' timezone
   information for those JDBC arguments which take a
   java.util.Calendar argument? (Notice that this option is exclusive
   of the "useTimezone=true" configuration option.) false 5.0.0
   useLegacyDatetimeCode Use code for DATE/TIME/DATETIME/TIMESTAMP
   handling in result sets and statements that consistently handles
   timezone conversions from client to server and back again, or use
   the legacy code for these datatypes that has been in the driver
   for backwards-compatibility? true 5.1.6
   useOldAliasMetadataBehavior Should the driver use the legacy
   behavior for "AS" clauses on columns and tables, and only return
   aliases (if any) for ResultSetMetaData.getColumnName() or
   ResultSetMetaData.getTableName() rather than the original
   column/table name? In 5.0.x, the default value was true. false
   5.0.4
   useOldUTF8Behavior Use the UTF-8 behavior the driver did when
   communicating with 4.0 and older servers false 3.1.6
   useOnlyServerErrorMessages Don't prepend 'standard' SQLState error
   messages to error messages returned by the server. true 3.0.15
   useSSPSCompatibleTimezoneShift If migrating from an environment
   that was using server-side prepared statements, and the
   configuration property "useJDBCCompliantTimeZoneShift" set to
   "true", use compatible behavior when not using server-side
   prepared statements when sending TIMESTAMP values to the MySQL
   server. false 5.0.5
   useServerPrepStmts Use server-side prepared statements if the
   server supports them? false 3.1.0
   useSqlStateCodes Use SQL Standard state codes instead of 'legacy'
   X/Open/SQL state codes (true/false), default is 'true' true 3.1.3
   useStreamLengthsInPrepStmts Honor stream length parameter in
   PreparedStatement/ResultSet.setXXXStream() method calls
   (true/false, defaults to 'true')? true 3.0.2
   useTimezone Convert time/date types between client and server
   timezones (true/false, defaults to 'false')? false 3.0.2
   useUnbufferedInput Don't use BufferedInputStream for reading data
   from the server true 3.0.11
   yearIsDateType Should the JDBC driver treat the MySQL type "YEAR"
   as a java.sql.Date, or as a SHORT? true 3.1.9
   zeroDateTimeBehavior What should happen when the driver encounters
   DATETIME values that are composed entirely of zeroes (used by
   MySQL to represent invalid dates)? Valid values are "exception",
   "round" and "convertToNull". exception 3.1.4

   Connector/J also supports access to MySQL via named pipes on
   Windows NT/2000/XP using the NamedPipeSocketFactory as a
   plugin-socket factory via the socketFactory property. If you do
   not use a namedPipePath property, the default of '\\.\pipe\MySQL'
   will be used. If you use the NamedPipeSocketFactory, the host name
   and port number values in the JDBC url will be ignored. You can
   enable this feature using:
socketFactory=com.mysql.jdbc.NamedPipeSocketFactory


   Named pipes only work when connecting to a MySQL server on the
   same physical machine as the one the JDBC driver is being used on.
   In simple performance tests, it appears that named pipe access is
   between 30%-50% faster than the standard TCP/IP access. However,
   this varies per system, and named pipes are slower than TCP/IP in
   many Windows configurations.

   You can create your own socket factories by following the example
   code in com.mysql.jdbc.NamedPipeSocketFactory, or
   com.mysql.jdbc.StandardSocketFactory.

4.2. JDBC API Implementation Notes

   MySQL Connector/J passes all of the tests in the publicly
   available version of Sun's JDBC compliance test suite. However, in
   many places the JDBC specification is vague about how certain
   functionality should be implemented, or the specification allows
   leeway in implementation.

   This section gives details on a interface-by-interface level about
   how certain implementation decisions may affect how you use MySQL
   Connector/J.

     * Blob
       Starting with Connector/J version 3.1.0, you can emulate Blobs
       with locators by adding the property 'emulateLocators=true' to
       your JDBC URL. Using this method, the driver will delay
       loading the actual Blob data until you retrieve the other data
       and then use retrieval methods (getInputStream(), getBytes(),
       and so forth) on the blob data stream.
       For this to work, you must use a column alias with the value
       of the column to the actual name of the Blob, for example:
SELECT id, 'data' as blob_data from blobtable
       For this to work, you must also follow these rules:

          + The SELECT
            (http://dev.mysql.com/doc/refman/5.0/en/select.html) must
            also reference only one table, the table must have a
            primary key.

          + The SELECT
            (http://dev.mysql.com/doc/refman/5.0/en/select.html) must
            alias the original blob column name, specified as a
            string, to an alternate name.

          + The SELECT
            (http://dev.mysql.com/doc/refman/5.0/en/select.html) must
            cover all columns that make up the primary key.
       The Blob implementation does not allow in-place modification
       (they are copies, as reported by the
       DatabaseMetaData.locatorsUpdateCopies() method). Because of
       this, you should use the corresponding
       PreparedStatement.setBlob() or ResultSet.updateBlob() (in the
       case of updatable result sets) methods to save changes back to
       the database.
       MySQL Enterprise MySQL Enterprise subscribers will find more
       information about type conversion in the Knowledge Base
       article, Type Conversions Supported by MySQL Connector/J
       (https://kb.mysql.com/view.php?id=4929). To subscribe to MySQL
       Enterprise see
       http://www.mysql.com/products/enterprise/advisors.html.

     * CallableStatement
       Starting with Connector/J 3.1.1, stored procedures are
       supported when connecting to MySQL version 5.0 or newer via
       the CallableStatement interface. Currently, the
       getParameterMetaData() method of CallableStatement is not
       supported.

     * Clob
       The Clob implementation does not allow in-place modification
       (they are copies, as reported by the
       DatabaseMetaData.locatorsUpdateCopies() method). Because of
       this, you should use the PreparedStatement.setClob() method to
       save changes back to the database. The JDBC API does not have
       a ResultSet.updateClob() method.

     * Connection
       Unlike older versions of MM.MySQL the isClosed() method does
       not ping the server to determine if it is alive. In accordance
       with the JDBC specification, it only returns true if closed()
       has been called on the connection. If you need to determine if
       the connection is still valid, you should issue a simple
       query, such as SELECT 1. The driver will throw an exception if
       the connection is no longer valid.

     * DatabaseMetaData
       Foreign Key information (getImportedKeys()/getExportedKeys()
       and getCrossReference()) is only available from InnoDB tables.
       However, the driver uses SHOW CREATE TABLE
       (http://dev.mysql.com/doc/refman/5.0/en/show-create-table.html
       ) to retrieve this information, so when other storage engines
       support foreign keys, the driver will transparently support
       them as well.

     * PreparedStatement
       PreparedStatements are implemented by the driver, as MySQL
       does not have a prepared statement feature. Because of this,
       the driver does not implement getParameterMetaData() or
       getMetaData() as it would require the driver to have a
       complete SQL parser in the client.
       Starting with version 3.1.0 MySQL Connector/J, server-side
       prepared statements and binary-encoded result sets are used
       when the server supports them.
       Take care when using a server-side prepared statement with
       large parameters that are set via setBinaryStream(),
       setAsciiStream(), setUnicodeStream(), setBlob(), or setClob().
       If you want to re-execute the statement with any large
       parameter changed to a nonlarge parameter, it is necessary to
       call clearParameters() and set all parameters again. The
       reason for this is as follows:

          + During both server-side prepared statements and
            client-side emulation, large data is exchanged only when
            PreparedStatement.execute() is called.

          + Once that has been done, the stream used to read the data
            on the client side is closed (as per the JDBC spec), and
            cannot be read from again.

          + If a parameter changes from large to nonlarge, the driver
            must reset the server-side state of the prepared
            statement to allow the parameter that is being changed to
            take the place of the prior large value. This removes all
            of the large data that has already been sent to the
            server, thus requiring the data to be re-sent, via the
            setBinaryStream(), setAsciiStream(), setUnicodeStream(),
            setBlob() or setClob() methods.
       Consequently, if you want to change the type of a parameter to
       a nonlarge one, you must call clearParameters() and set all
       parameters of the prepared statement again before it can be
       re-executed.

     * ResultSet
       By default, ResultSets are completely retrieved and stored in
       memory. In most cases this is the most efficient way to
       operate, and due to the design of the MySQL network protocol
       is easier to implement. If you are working with ResultSets
       that have a large number of rows or large values, and can not
       allocate heap space in your JVM for the memory required, you
       can tell the driver to stream the results back one row at a
       time.
       To enable this functionality, you need to create a Statement
       instance in the following manner:
stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY,
              java.sql.ResultSet.CONCUR_READ_ONLY);
stmt.setFetchSize(Integer.MIN_VALUE);
       The combination of a forward-only, read-only result set, with
       a fetch size of Integer.MIN_VALUE serves as a signal to the
       driver to stream result sets row-by-row. After this any result
       sets created with the statement will be retrieved row-by-row.
       There are some caveats with this approach. You will have to
       read all of the rows in the result set (or close it) before
       you can issue any other queries on the connection, or an
       exception will be thrown.
       The earliest the locks these statements hold can be released
       (whether they be MyISAM table-level locks or row-level locks
       in some other storage engine such as InnoDB) is when the
       statement completes.
       If the statement is within scope of a transaction, then locks
       are released when the transaction completes (which implies
       that the statement needs to complete first). As with most
       other databases, statements are not complete until all the
       results pending on the statement are read or the active result
       set for the statement is closed.
       Therefore, if using streaming results, you should process them
       as quickly as possible if you want to maintain concurrent
       access to the tables referenced by the statement producing the
       result set.

     * ResultSetMetaData
       The isAutoIncrement() method only works when using MySQL
       servers 4.0 and newer.

     * Statement
       When using versions of the JDBC driver earlier than 3.2.1, and
       connected to server versions earlier than 5.0.3, the
       setFetchSize() method has no effect, other than to toggle
       result set streaming as described above.
       Connector/J 5.0.0 and later include support for both
       Statement.cancel() and Statement.setQueryTimeout(). Both
       require MySQL 5.0.0 or newer server, and require a separate
       connection to issue the KILL QUERY
       (http://dev.mysql.com/doc/refman/5.0/en/kill.html) statement.
       In the case of setQueryTimeout(), the implementation creates
       an additional thread to handle the timeout functionality.

Note
       Failures to cancel the statement for setQueryTimeout() may
       manifest themselves as RuntimeException rather than failing
       silently, as there is currently no way to unblock the thread
       that is executing the query being cancelled due to timeout
       expiration and have it throw the exception instead.
       MySQL does not support SQL cursors, and the JDBC driver
       doesn't emulate them, so "setCursorName()" has no effect.
       Connector/J 5.1.3 and later include two additional methods:

          + setLocalInfileInputStream() sets an InputStream instance
            that will be used to send data to the MySQL server for a
            LOAD DATA LOCAL INFILE
            (http://dev.mysql.com/doc/refman/5.0/en/load-data.html)
            statement rather than a FileInputStream or URLInputStream
            that represents the path given as an argument to the
            statement.
            This stream will be read to completion upon execution of
            a LOAD DATA LOCAL INFILE
            (http://dev.mysql.com/doc/refman/5.0/en/load-data.html)
            statement, and will automatically be closed by the
            driver, so it needs to be reset before each call to
            execute*() that would cause the MySQL server to request
            data to fulfill the request for LOAD DATA LOCAL INFILE
            (http://dev.mysql.com/doc/refman/5.0/en/load-data.html).
            If this value is set to NULL, the driver will revert to
            using a FileInputStream or URLInputStream as required.

          + getLocalInfileInputStream() returns the InputStream
            instance that will be used to send data in response to a
            LOAD DATA LOCAL INFILE
            (http://dev.mysql.com/doc/refman/5.0/en/load-data.html)
            statement.
            This method returns NULL if no such stream has been set
            via setLocalInfileInputStream().

4.3. Java, JDBC and MySQL Types

   MySQL Connector/J is flexible in the way it handles conversions
   between MySQL data types and Java data types.

   In general, any MySQL data type can be converted to a
   java.lang.String, and any numerical type can be converted to any
   of the Java numerical types, although round-off, overflow, or loss
   of precision may occur.

   Starting with Connector/J 3.1.0, the JDBC driver will issue
   warnings or throw DataTruncation exceptions as is required by the
   JDBC specification unless the connection was configured not to do
   so by using the property jdbcCompliantTruncation and setting it to
   false.

   The conversions that are always guaranteed to work are listed in
   the following table:

   Connection Properties - Miscellaneous. 
   These MySQL Data Types Can always be converted to these Java types
   CHAR, VARCHAR, BLOB, TEXT, ENUM, and SET java.lang.String,
   java.io.InputStream, java.io.Reader, java.sql.Blob, java.sql.Clob
   FLOAT, REAL, DOUBLE PRECISION, NUMERIC, DECIMAL, TINYINT,
   SMALLINT, MEDIUMINT, INTEGER, BIGINT java.lang.String,
   java.lang.Short, java.lang.Integer, java.lang.Long,
   java.lang.Double, java.math.BigDecimal
   DATE, TIME, DATETIME, TIMESTAMP java.lang.String, java.sql.Date,
   java.sql.Timestamp

Note

   Round-off, overflow or loss of precision may occur if you choose a
   Java numeric data type that has less precision or capacity than
   the MySQL data type you are converting to/from.

   The ResultSet.getObject() method uses the type conversions between
   MySQL and Java types, following the JDBC specification where
   appropriate. The value returned by
   ResultSetMetaData.GetColumnClassName() is also shown below. For
   more information on the java.sql.Types classes see Java 2 Platform
   Types
   (http://java.sun.com/j2se/1.4.2/docs/api/java/sql/Types.html).

   MySQL Types to Java Types for ResultSet.getObject(). 
   MySQL Type Name Return value of GetColumnClassName Returned as
   Java Class
   BIT(1) (new in MySQL-5.0) BIT java.lang.Boolean
   BIT( > 1) (new in MySQL-5.0) BIT byte[]
   TINYINT TINYINT java.lang.Boolean if the configuration property
   tinyInt1isBit is set to true (the default) and the storage size is
   1, or java.lang.Integer if not.
   BOOL, BOOLEAN TINYINT See TINYINT, above as these are aliases for
   TINYINT(1), currently.
   SMALLINT[(M)] [UNSIGNED] SMALLINT [UNSIGNED] java.lang.Integer
   (regardless if UNSIGNED or not)
   MEDIUMINT[(M)] [UNSIGNED] MEDIUMINT [UNSIGNED] java.lang.Integer,
   if UNSIGNED java.lang.Long (C/J 3.1 and earlier), or
   java.lang.Integer for C/J 5.0 and later
   INT,INTEGER[(M)] [UNSIGNED] INTEGER [UNSIGNED] java.lang.Integer,
   if UNSIGNED java.lang.Long
   BIGINT[(M)] [UNSIGNED] BIGINT [UNSIGNED] java.lang.Long, if
   UNSIGNED java.math.BigInteger
   FLOAT[(M,D)] FLOAT java.lang.Float
   DOUBLE[(M,B)] DOUBLE java.lang.Double
   DECIMAL[(M[,D])] DECIMAL java.math.BigDecimal
   DATE DATE java.sql.Date
   DATETIME DATETIME java.sql.Timestamp
   TIMESTAMP[(M)] TIMESTAMP java.sql.Timestamp
   TIME TIME java.sql.Time
   YEAR[(2|4)] YEAR If yearIsDateType configuration property is set
   to false, then the returned object type is java.sql.Short. If set
   to true (the default) then an object of type java.sql.Date (with
   the date set to January 1st, at midnight).
   CHAR(M) CHAR java.lang.String (unless the character set for the
   column is BINARY, then byte[] is returned.
   VARCHAR(M) [BINARY] VARCHAR java.lang.String (unless the character
   set for the column is BINARY, then byte[] is returned.
   BINARY(M) BINARY byte[]
   VARBINARY(M) VARBINARY byte[]
   TINYBLOB TINYBLOB byte[]
   TINYTEXT VARCHAR java.lang.String
   BLOB BLOB byte[]
   TEXT VARCHAR java.lang.String
   MEDIUMBLOB MEDIUMBLOB byte[]
   MEDIUMTEXT VARCHAR java.lang.String
   LONGBLOB LONGBLOB byte[]
   LONGTEXT VARCHAR java.lang.String
   ENUM('value1','value2',...) CHAR java.lang.String
   SET('value1','value2',...) CHAR java.lang.String

4.4. Using Character Sets and Unicode

   All strings sent from the JDBC driver to the server are converted
   automatically from native Java Unicode form to the client
   character encoding, including all queries sent via
   Statement.execute(), Statement.executeUpdate(),
   Statement.executeQuery() as well as all PreparedStatement and
   CallableStatement parameters with the exclusion of parameters set
   using setBytes(), setBinaryStream(), setAsciiStream(),
   setUnicodeStream() and setBlob().

   Prior to MySQL Server 4.1, Connector/J supported a single
   character encoding per connection, which could either be
   automatically detected from the server configuration, or could be
   configured by the user through the useUnicode and
   characterEncoding properties.

   Starting with MySQL Server 4.1, Connector/J supports a single
   character encoding between client and server, and any number of
   character encodings for data returned by the server to the client
   in ResultSets.

   The character encoding between client and server is automatically
   detected upon connection. The encoding used by the driver is
   specified on the server via the character_set system variable for
   server versions older than 4.1.0 and character_set_server
   (http://dev.mysql.com/doc/refman/5.0/en/server-system-variables.ht
   ml#sysvar_character_set_server) for server versions 4.1.0 and
   newer. For more information, see Server Character Set and
   Collation
   (http://dev.mysql.com/doc/refman/5.0/en/charset-syntax.html#charse
   t-server).

   To override the automatically detected encoding on the client
   side, use the characterEncoding property in the URL used to
   connect to the server.

   When specifying character encodings on the client side, Java-style
   names should be used. The following table lists Java-style names
   for MySQL character sets:

   MySQL to Java Encoding Name Translations. 
   MySQL Character Set Name Java-Style Character Encoding Name
   ascii US-ASCII
   big5 Big5
   gbk GBK
   sjis SJIS (or Cp932 or MS932 for MySQL Server < 4.1.11)
   cp932 Cp932 or MS932 (MySQL Server > 4.1.11)
   gb2312 EUC_CN
   ujis EUC_JP
   euckr EUC_KR
   latin1 ISO8859_1
   latin2 ISO8859_2
   greek ISO8859_7
   hebrew ISO8859_8
   cp866 Cp866
   tis620 TIS620
   cp1250 Cp1250
   cp1251 Cp1251
   cp1257 Cp1257
   macroman MacRoman
   macce MacCentralEurope
   utf8 UTF-8
   ucs2 UnicodeBig

Warning

   Do not issue the query 'set names' with Connector/J, as the driver
   will not detect that the character set has changed, and will
   continue to use the character set detected during the initial
   connection setup.

   To allow multiple character sets to be sent from the client, the
   UTF-8 encoding should be used, either by configuring utf8 as the
   default server character set, or by configuring the JDBC driver to
   use UTF-8 through the characterEncoding property.

4.5. Connecting Securely Using SSL

   SSL in MySQL Connector/J encrypts all data (other than the initial
   handshake) between the JDBC driver and the server. The performance
   penalty for enabling SSL is an increase in query processing time
   between 35% and 50%, depending on the size of the query, and the
   amount of data it returns.

   For SSL Support to work, you must have the following:

     * A JDK that includes JSSE (Java Secure Sockets Extension), like
       JDK-1.4.1 or newer. SSL does not currently work with a JDK
       that you can add JSSE to, like JDK-1.2.x or JDK-1.3.x due to
       the following JSSE bug:
       http://developer.java.sun.com/developer/bugParade/bugs/4273544
       .html

     * A MySQL server that supports SSL and has been compiled and
       configured to do so, which is MySQL-4.0.4 or later, see Using
       SSL for Secure Connections
       (http://dev.mysql.com/doc/refman/5.0/en/secure-connections.htm
       l), for more information.

     * A client certificate (covered later in this section)

   The system works through two Java truststore files, one file
   contains the certificate information for the server (truststore in
   the examples below). The other file contains the certificate for
   the client (keystore in the examples below). All Java truststore
   files are password protected by supplying a suitable password to
   the keytool when you create the files. You need the file names and
   associated passwords to create an SSL connection.

   You will first need to import the MySQL server CA Certificate into
   a Java truststore. A sample MySQL server CA Certificate is located
   in the SSL subdirectory of the MySQL source distribution. This is
   what SSL will use to determine if you are communicating with a
   secure MySQL server. Alternatively, use the CA Certificate that
   you have generated or been provided with by your SSL provider.

   To use Java's keytool to create a truststore in the current
   directory , and import the server's CA certificate (cacert.pem),
   you can do the following (assuming that keytool is in your path.
   The keytool should be located in the bin subdirectory of your JDK
   or JRE):
shell> keytool -import -alias mysqlServerCACert \
                                  -file cacert.pem -keystore truststo
re

   You will need to enter the password when prompted for the keystore
   file. Interaction with keytool will look like this:
Enter keystore password:  *********
Owner: EMAILADDRESS=walrus@example.com, CN=Walrus,
       O=MySQL AB, L=Orenburg, ST=Some-State, C=RU
Issuer: EMAILADDRESS=walrus@example.com, CN=Walrus,
       O=MySQL AB, L=Orenburg, ST=Some-State, C=RU
Serial number: 0
Valid from:
   Fri Aug 02 16:55:53 CDT 2002 until: Sat Aug 02 16:55:53 CDT 2003
Certificate fingerprints:
    MD5:  61:91:A0:F2:03:07:61:7A:81:38:66:DA:19:C4:8D:AB
    SHA1: 25:77:41:05:D5:AD:99:8C:14:8C:CA:68:9C:2F:B8:89:C3:34:4D:6C
Trust this certificate? [no]:  yes
Certificate was added to keystore

   You then have two options, you can either import the client
   certificate that matches the CA certificate you just imported, or
   you can create a new client certificate.

   To import an existing certificate, the certificate should be in
   DER format. You can use openssl to convert an existing certificate
   into the new format. For example:
shell> openssl x509 -outform DER -in client-cert.pem -out client.cert


   You now need to import the converted certificate into your
   keystore using keytool:
shell> keytool -import -file client.cert -keystore keystore -alias my
sqlClientCertificate

   To generate your own client certificate, use keytool to create a
   suitable certificate and add it to the keystore file:
 shell> keytool -genkey -keyalg rsa \
     -alias mysqlClientCertificate -keystore keystore

   Keytool will prompt you for the following information, and create
   a keystore named keystore in the current directory.

   You should respond with information that is appropriate for your
   situation:
Enter keystore password:  *********
What is your first and last name?
  [Unknown]:  Matthews
What is the name of your organizational unit?
  [Unknown]:  Software Development
What is the name of your organization?
  [Unknown]:  MySQL AB
What is the name of your City or Locality?
  [Unknown]:  Flossmoor
What is the name of your State or Province?
  [Unknown]:  IL
What is the two-letter country code for this unit?
  [Unknown]:  US
Is <CN=Matthews, OU=Software Development, O=MySQL AB,
 L=Flossmoor, ST=IL, C=US> correct?
  [no]:  y
Enter key password for <mysqlClientCertificate>
        (RETURN if same as keystore password):

   Finally, to get JSSE to use the keystore and truststore that you
   have generated, you need to set the following system properties
   when you start your JVM, replacing path_to_keystore_file with the
   full path to the keystore file you created,
   path_to_truststore_file with the path to the truststore file you
   created, and using the appropriate password values for each
   property. You can do this either on the command line:
-Djavax.net.ssl.keyStore=path_to_keystore_file
-Djavax.net.ssl.keyStorePassword=password
-Djavax.net.ssl.trustStore=path_to_truststore_file
-Djavax.net.ssl.trustStorePassword=password

   Or you can set the values directly within the application:
 System.setProperty("javax.net.ssl.keyStore","path_to_keystore_file")
;
System.setProperty("javax.net.ssl.keyStorePassword","password");
System.setProperty("javax.net.ssl.trustStore","path_to_truststore_fil
e");
System.setProperty("javax.net.ssl.trustStorePassword","password");

   You will also need to set useSSL to true in your connection
   parameters for MySQL Connector/J, either by adding useSSL=true to
   your URL, or by setting the property useSSL to true in the
   java.util.Properties instance you pass to
   DriverManager.getConnection().

   You can test that SSL is working by turning on JSSE debugging (as
   detailed below), and look for the following key events:
...
*** ClientHello, v3.1
RandomCookie:  GMT: 1018531834 bytes = { 199, 148, 180, 215, 74, 12,
??
  54, 244, 0, 168, 55, 103, 215, 64, 16, 138, 225, 190, 132, 153, 2,
??
  217, 219, 239, 202, 19, 121, 78 }
Session ID:  {}
Cipher Suites:  { 0, 5, 0, 4, 0, 9, 0, 10, 0, 18, 0, 19, 0, 3, 0, 17
}
Compression Methods:  { 0 }
***
[write] MD5 and SHA1 hashes:  len = 59
0000: 01 00 00 37 03 01 3D B6 90 FA C7 94 B4 D7 4A 0C  ...7..=.......
J.
0010: 36 F4 00 A8 37 67 D7 40 10 8A E1 BE 84 99 02 D9  6...7g.@......
..
0020: DB EF CA 13 79 4E 00 00 10 00 05 00 04 00 09 00  ....yN........
..
0030: 0A 00 12 00 13 00 03 00 11 01 00                 ...........
main, WRITE:  SSL v3.1 Handshake, length = 59
main, READ:  SSL v3.1 Handshake, length = 74
*** ServerHello, v3.1
RandomCookie:  GMT: 1018577560 bytes = { 116, 50, 4, 103, 25, 100, 58
, ??
   202, 79, 185, 178, 100, 215, 66, 254, 21, 83, 187, 190, 42, 170, 3
, ??
   132, 110, 82, 148, 160, 92 }
Session ID:  {163, 227, 84, 53, 81, 127, 252, 254, 178, 179, 68, 63,
??
   182, 158, 30, 11, 150, 79, 170, 76, 255, 92, 15, 226, 24, 17, 177,
 ??
   219, 158, 177, 187, 143}
Cipher Suite:  { 0, 5 }
Compression Method: 0
***
%% Created:  [Session-1, SSL_RSA_WITH_RC4_128_SHA]
** SSL_RSA_WITH_RC4_128_SHA
[read] MD5 and SHA1 hashes:  len = 74
0000: 02 00 00 46 03 01 3D B6 43 98 74 32 04 67 19 64  ...F..=.C.t2.g
.d
0010: 3A CA 4F B9 B2 64 D7 42 FE 15 53 BB BE 2A AA 03  :.O..d.B..S..*
..
0020: 84 6E 52 94 A0 5C 20 A3 E3 54 35 51 7F FC FE B2  .nR..\ ..T5Q..
..
0030: B3 44 3F B6 9E 1E 0B 96 4F AA 4C FF 5C 0F E2 18  .D?.....O.L.\.
..
0040: 11 B1 DB 9E B1 BB 8F 00 05 00                    ..........
main, READ:  SSL v3.1 Handshake, length = 1712
...

   JSSE provides debugging (to STDOUT) when you set the following
   system property: -Djavax.net.debug=all This will tell you what
   keystores and truststores are being used, as well as what is going
   on during the SSL handshake and certificate exchange. It will be
   helpful when trying to determine what is not working when trying
   to get an SSL connection to happen.

4.6. Using Master/Slave Replication with ReplicationConnection

   Starting with Connector/J 3.1.7, we've made available a variant of
   the driver that will automatically send queries to a read/write
   master, or a failover or round-robin loadbalanced set of slaves
   based on the state of Connection.getReadOnly() .

   An application signals that it wants a transaction to be read-only
   by calling Connection.setReadOnly(true), this replication-aware
   connection will use one of the slave connections, which are
   load-balanced per-vm using a round-robin scheme (a given
   connection is sticky to a slave unless that slave is removed from
   service). If you have a write transaction, or if you have a read
   that is time-sensitive (remember, replication in MySQL is
   asynchronous), set the connection to be not read-only, by calling
   Connection.setReadOnly(false) and the driver will ensure that
   further calls are sent to the master MySQL server. The driver
   takes care of propagating the current state of autocommit,
   isolation level, and catalog between all of the connections that
   it uses to accomplish this load balancing functionality.

   To enable this functionality, use the "
   com.mysql.jdbc.ReplicationDriver " class when configuring your
   application server's connection pool or when creating an instance
   of a JDBC driver for your standalone application. Because it
   accepts the same URL format as the standard MySQL JDBC driver,
   ReplicationDriver does not currently work with
   java.sql.DriverManager -based connection creation unless it is the
   only MySQL JDBC driver registered with the DriverManager .

   Here is a short, simple example of how ReplicationDriver might be
   used in a standalone application.
import java.sql.Connection;
import java.sql.ResultSet;
import java.util.Properties;
import com.mysql.jdbc.ReplicationDriver;
public class ReplicationDriverDemo {
  public static void main(String[] args) throws Exception {
    ReplicationDriver driver = new ReplicationDriver();
    Properties props = new Properties();
    // We want this for failover on the slaves
    props.put("autoReconnect", "true");
    // We want to load balance between the slaves
    props.put("roundRobinLoadBalance", "true");
    props.put("user", "foo");
    props.put("password", "bar");
    //
    // Looks like a normal MySQL JDBC url, with a
    // comma-separated list of hosts, the first
    // being the 'master', the rest being any number
    // of slaves that the driver will load balance against
    //
    Connection conn =
        driver.connect("jdbc:mysql://master,slave1,slave2,slave3/test
",
            props);
    //
    // Perform read/write work on the master
    // by setting the read-only flag to "false"
    //
    conn.setReadOnly(false);
    conn.setAutoCommit(false);
    conn.createStatement().executeUpdate("UPDATE some_table ....");
    conn.commit();
    //
    // Now, do a query from a slave, the driver automatically picks o
ne
    // from the list
    //
    conn.setReadOnly(true);
    ResultSet rs =
      conn.createStatement().executeQuery("SELECT a,b FROM alt_table"
);
     .......
  }
}

   You may also want to investigate the Load Balancing JDBC Pool
   (lbpol) tool, which provides a wrapper around the standard JDBC
   driver and allows you to use DB connection pools that includes
   checks for system failures and uneven load distribution. For more
   information, see Load Balancing JDBC Pool (lbpool)
   (http://code.tailrank.com/lbpool).

4.7. Mapping MySQL Error Numbers to SQLStates

   The table below provides a mapping of the MySQL Error Numbers to
   SQL States

   Table 4.1. Mapping of MySQL Error Numbers to SQLStates
   MySQL Error Number MySQL Error Name Legacy (X/Open) SQLState SQL
   Standard SQLState
   1022 ER_DUP_KEY S1000 23000
   1037 ER_OUTOFMEMORY S1001 HY001
   1038 ER_OUT_OF_SORTMEMORY S1001 HY001
   1040 ER_CON_COUNT_ERROR 08004 08004
   1042 ER_BAD_HOST_ERROR 08004 08S01
   1043 ER_HANDSHAKE_ERROR 08004 08S01
   1044 ER_DBACCESS_DENIED_ERROR S1000 42000
   1045 ER_ACCESS_DENIED_ERROR 28000 28000
   1047 ER_UNKNOWN_COM_ERROR 08S01 HY000
   1050 ER_TABLE_EXISTS_ERROR S1000 42S01
   1051 ER_BAD_TABLE_ERROR 42S02 42S02
   1052 ER_NON_UNIQ_ERROR S1000 23000
   1053 ER_SERVER_SHUTDOWN S1000 08S01
   1054 ER_BAD_FIELD_ERROR S0022 42S22
   1055 ER_WRONG_FIELD_WITH_GROUP S1009 42000
   1056 ER_WRONG_GROUP_FIELD S1009 42000
   1057 ER_WRONG_SUM_SELECT S1009 42000
   1058 ER_WRONG_VALUE_COUNT 21S01 21S01
   1059 ER_TOO_LONG_IDENT S1009 42000
   1060 ER_DUP_FIELDNAME S1009 42S21
   1061 ER_DUP_KEYNAME S1009 42000
   1062 ER_DUP_ENTRY S1009 23000
   1063 ER_WRONG_FIELD_SPEC S1009 42000
   1064 ER_PARSE_ERROR 42000 42000
   1065 ER_EMPTY_QUERY 42000 42000
   1066 ER_NONUNIQ_TABLE S1009 42000
   1067 ER_INVALID_DEFAULT S1009 42000
   1068 ER_MULTIPLE_PRI_KEY S1009 42000
   1069 ER_TOO_MANY_KEYS S1009 42000
   1070 ER_TOO_MANY_KEY_PARTS S1009 42000
   1071 ER_TOO_LONG_KEY S1009 42000
   1072 ER_KEY_COLUMN_DOES_NOT_EXITS S1009 42000
   1073 ER_BLOB_USED_AS_KEY S1009 42000
   1074 ER_TOO_BIG_FIELDLENGTH S1009 42000
   1075 ER_WRONG_AUTO_KEY S1009 42000
   1080 ER_FORCING_CLOSE S1000 08S01
   1081 ER_IPSOCK_ERROR 08S01 08S01
   1082 ER_NO_SUCH_INDEX S1009 42S12
   1083 ER_WRONG_FIELD_TERMINATORS S1009 42000
   1084 ER_BLOBS_AND_NO_TERMINATED S1009 42000
   1090 ER_CANT_REMOVE_ALL_FIELDS S1000 42000
   1091 ER_CANT_DROP_FIELD_OR_KEY S1000 42000
   1101 ER_BLOB_CANT_HAVE_DEFAULT S1000 42000
   1102 ER_WRONG_DB_NAME S1000 42000
   1103 ER_WRONG_TABLE_NAME S1000 42000
   1104 ER_TOO_BIG_SELECT S1000 42000
   1106 ER_UNKNOWN_PROCEDURE S1000 42000
   1107 ER_WRONG_PARAMCOUNT_TO_PROCEDURE S1000 42000
   1109 ER_UNKNOWN_TABLE S1000 42S02
   1110 ER_FIELD_SPECIFIED_TWICE S1000 42000
   1112 ER_UNSUPPORTED_EXTENSION S1000 42000
   1113 ER_TABLE_MUST_HAVE_COLUMNS S1000 42000
   1115 ER_UNKNOWN_CHARACTER_SET S1000 42000
   1118 ER_TOO_BIG_ROWSIZE S1000 42000
   1120 ER_WRONG_OUTER_JOIN S1000 42000
   1121 ER_NULL_COLUMN_IN_INDEX S1000 42000
   1129 ER_HOST_IS_BLOCKED 08004 HY000
   1130 ER_HOST_NOT_PRIVILEGED 08004 HY000
   1131 ER_PASSWORD_ANONYMOUS_USER S1000 42000
   1132 ER_PASSWORD_NOT_ALLOWED S1000 42000
   1133 ER_PASSWORD_NO_MATCH S1000 42000
   1136 ER_WRONG_VALUE_COUNT_ON_ROW S1000 21S01
   1138 ER_INVALID_USE_OF_NULL S1000 42000
   1139 ER_REGEXP_ERROR S1000 42000
   1140 ER_MIX_OF_GROUP_FUNC_AND_FIELDS S1000 42000
   1141 ER_NONEXISTING_GRANT S1000 42000
   1142 ER_TABLEACCESS_DENIED_ERROR S1000 42000
   1143 ER_COLUMNACCESS_DENIED_ERROR S1000 42000
   1144 ER_ILLEGAL_GRANT_FOR_TABLE S1000 42000
   1145 ER_GRANT_WRONG_HOST_OR_USER S1000 42000
   1146 ER_NO_SUCH_TABLE S1000 42S02
   1147 ER_NONEXISTING_TABLE_GRANT S1000 42000
   1148 ER_NOT_ALLOWED_COMMAND S1000 42000
   1149 ER_SYNTAX_ERROR S1000 42000
   1152 ER_ABORTING_CONNECTION S1000 08S01
   1153 ER_NET_PACKET_TOO_LARGE S1000 08S01
   1154 ER_NET_READ_ERROR_FROM_PIPE S1000 08S01
   1155 ER_NET_FCNTL_ERROR S1000 08S01
   1156 ER_NET_PACKETS_OUT_OF_ORDER S1000 08S01
   1157 ER_NET_UNCOMPRESS_ERROR S1000 08S01
   1158 ER_NET_READ_ERROR S1000 08S01
   1159 ER_NET_READ_INTERRUPTED S1000 08S01
   1160 ER_NET_ERROR_ON_WRITE S1000 08S01
   1161 ER_NET_WRITE_INTERRUPTED S1000 08S01
   1162 ER_TOO_LONG_STRING S1000 42000
   1163 ER_TABLE_CANT_HANDLE_BLOB S1000 42000
   1164 ER_TABLE_CANT_HANDLE_AUTO_INCREMENT S1000 42000
   1166 ER_WRONG_COLUMN_NAME S1000 42000
   1167 ER_WRONG_KEY_COLUMN S1000 42000
   1169 ER_DUP_UNIQUE S1000 23000
   1170 ER_BLOB_KEY_WITHOUT_LENGTH S1000 42000
   1171 ER_PRIMARY_CANT_HAVE_NULL S1000 42000
   1172 ER_TOO_MANY_ROWS S1000 42000
   1173 ER_REQUIRES_PRIMARY_KEY S1000 42000
   1177 ER_CHECK_NO_SUCH_TABLE S1000 42000
   1178 ER_CHECK_NOT_IMPLEMENTED S1000 42000
   1179 ER_CANT_DO_THIS_DURING_AN_TRANSACTION S1000 25000
   1184 ER_NEW_ABORTING_CONNECTION S1000 08S01
   1189 ER_MASTER_NET_READ S1000 08S01
   1190 ER_MASTER_NET_WRITE S1000 08S01
   1203 ER_TOO_MANY_USER_CONNECTIONS S1000 42000
   1205 ER_LOCK_WAIT_TIMEOUT 41000 41000
   1207 ER_READ_ONLY_TRANSACTION S1000 25000
   1211 ER_NO_PERMISSION_TO_CREATE_USER S1000 42000
   1213 ER_LOCK_DEADLOCK 41000 40001
   1216 ER_NO_REFERENCED_ROW S1000 23000
   1217 ER_ROW_IS_REFERENCED S1000 23000
   1218 ER_CONNECT_TO_MASTER S1000 08S01
   1222 ER_WRONG_NUMBER_OF_COLUMNS_IN_SELECT S1000 21000
   1226 ER_USER_LIMIT_REACHED S1000 42000
   1230 ER_NO_DEFAULT S1000 42000
   1231 ER_WRONG_VALUE_FOR_VAR S1000 42000
   1232 ER_WRONG_TYPE_FOR_VAR S1000 42000
   1234 ER_CANT_USE_OPTION_HERE S1000 42000
   1235 ER_NOT_SUPPORTED_YET S1000 42000
   1239 ER_WRONG_FK_DEF S1000 42000
   1241 ER_OPERAND_COLUMNS S1000 21000
   1242 ER_SUBQUERY_NO_1_ROW S1000 21000
   1247 ER_ILLEGAL_REFERENCE S1000 42S22
   1248 ER_DERIVED_MUST_HAVE_ALIAS S1000 42000
   1249 ER_SELECT_REDUCED S1000 01000
   1250 ER_TABLENAME_NOT_ALLOWED_HERE S1000 42000
   1251 ER_NOT_SUPPORTED_AUTH_MODE S1000 08004
   1252 ER_SPATIAL_CANT_HAVE_NULL S1000 42000
   1253 ER_COLLATION_CHARSET_MISMATCH S1000 42000
   1261 ER_WARN_TOO_FEW_RECORDS S1000 01000
   1262 ER_WARN_TOO_MANY_RECORDS S1000 01000
   1263 ER_WARN_NULL_TO_NOTNULL S1000 01000
   1264 ER_WARN_DATA_OUT_OF_RANGE S1000 01000
   1265 ER_WARN_DATA_TRUNCATED S1000 01000
   1280 ER_WRONG_NAME_FOR_INDEX S1000 42000
   1281 ER_WRONG_NAME_FOR_CATALOG S1000 42000
   1286 ER_UNKNOWN_STORAGE_ENGINE S1000 42000

Chapter 5. Connector/J Notes and Tips

5.1. Basic JDBC Concepts

   This section provides some general JDBC background.

5.1.1. Connecting to MySQL Using the DriverManager Interface

   When you are using JDBC outside of an application server, the
   DriverManager class manages the establishment of Connections.

   The DriverManager needs to be told which JDBC drivers it should
   try to make Connections with. The easiest way to do this is to use
   Class.forName() on the class that implements the java.sql.Driver
   interface. With MySQL Connector/J, the name of this class is
   com.mysql.jdbc.Driver. With this method, you could use an external
   configuration file to supply the driver class name and driver
   parameters to use when connecting to a database.

   The following section of Java code shows how you might register
   MySQL Connector/J from the main() method of your application:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
// Notice, do not import com.mysql.jdbc.*
// or you will have problems!
public class LoadDriver {
    public static void main(String[] args) {
        try {
            // The newInstance() call is a work around for some
            // broken Java implementations
            Class.forName("com.mysql.jdbc.Driver").newInstance();
        } catch (Exception ex) {
            // handle the error
        }
    }
}

   After the driver has been registered with the DriverManager, you
   can obtain a Connection instance that is connected to a particular
   database by calling DriverManager.getConnection():

   Example 5.1. Connector/J: Obtaining a connection from the
   DriverManager

   This example shows how you can obtain a Connection instance from
   the DriverManager. There are a few different signatures for the
   getConnection() method. You should see the API documentation that
   comes with your JDK for more specific information on how to use
   them.
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
Connection conn = null;
...
try {
    conn =
       DriverManager.getConnection("jdbc:mysql://localhost/test?" +
                                   "user=monty&password=greatsqldb");
    // Do something with the Connection
   ...
} catch (SQLException ex) {
    // handle any errors
    System.out.println("SQLException: " + ex.getMessage());
    System.out.println("SQLState: " + ex.getSQLState());
    System.out.println("VendorError: " + ex.getErrorCode());
}

   Once a Connection is established, it can be used to create
   Statement and PreparedStatement objects, as well as retrieve
   metadata about the database. This is explained in the following
   sections.

5.1.2. Using Statements to Execute SQL

   Statement objects allow you to execute basic SQL queries and
   retrieve the results through the ResultSet class which is
   described later.

   To create a Statement instance, you call the createStatement()
   method on the Connection object you have retrieved via one of the
   DriverManager.getConnection() or DataSource.getConnection()
   methods described earlier.

   Once you have a Statement instance, you can execute a SELECT
   (http://dev.mysql.com/doc/refman/5.0/en/select.html) query by
   calling the executeQuery(String) method with the SQL you want to
   use.

   To update data in the database, use the executeUpdate(String SQL)
   method. This method returns the number of rows affected by the
   update statement.

   If you do not know ahead of time whether the SQL statement will be
   a SELECT (http://dev.mysql.com/doc/refman/5.0/en/select.html) or
   an UPDATE
   (http://dev.mysql.com/doc/refman/5.0/en/update.html)/INSERT
   (http://dev.mysql.com/doc/refman/5.0/en/insert.html), then you can
   use the execute(String SQL) method. This method will return true
   if the SQL query was a SELECT
   (http://dev.mysql.com/doc/refman/5.0/en/select.html), or false if
   it was an UPDATE
   (http://dev.mysql.com/doc/refman/5.0/en/update.html), INSERT
   (http://dev.mysql.com/doc/refman/5.0/en/insert.html), or DELETE
   (http://dev.mysql.com/doc/refman/5.0/en/delete.html) statement. If
   the statement was a SELECT
   (http://dev.mysql.com/doc/refman/5.0/en/select.html) query, you
   can retrieve the results by calling the getResultSet() method. If
   the statement was an UPDATE
   (http://dev.mysql.com/doc/refman/5.0/en/update.html), INSERT
   (http://dev.mysql.com/doc/refman/5.0/en/insert.html), or DELETE
   (http://dev.mysql.com/doc/refman/5.0/en/delete.html) statement,
   you can retrieve the affected rows count by calling
   getUpdateCount() on the Statement instance.

   Example 5.2. Connector/J: Using java.sql.Statement to execute a
   SELECT query
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.ResultSet;
// assume that conn is an already created JDBC connection (see previo
us examples)
Statement stmt = null;
ResultSet rs = null;
try {
    stmt = conn.createStatement();
    rs = stmt.executeQuery("SELECT foo FROM bar");
    // or alternatively, if you don't know ahead of time that
    // the query will be a SELECT...
    if (stmt.execute("SELECT foo FROM bar")) {
        rs = stmt.getResultSet();
    }
    // Now do something with the ResultSet ....
}
catch (SQLException ex){
    // handle any errors
    System.out.println("SQLException: " + ex.getMessage());
    System.out.println("SQLState: " + ex.getSQLState());
    System.out.println("VendorError: " + ex.getErrorCode());
}
finally {
    // it is a good idea to release
    // resources in a finally{} block
    // in reverse-order of their creation
    // if they are no-longer needed
    if (rs != null) {
        try {
            rs.close();
        } catch (SQLException sqlEx) { } // ignore
        rs = null;
    }
    if (stmt != null) {
        try {
            stmt.close();
        } catch (SQLException sqlEx) { } // ignore
        stmt = null;
    }
}

5.1.3. Using CallableStatements to Execute Stored Procedures

   Starting with MySQL server version 5.0 when used with Connector/J
   3.1.1 or newer, the java.sql.CallableStatement interface is fully
   implemented with the exception of the getParameterMetaData()
   method.

   For more information on MySQL stored procedures, please refer to
   http://dev.mysql.com/doc/mysql/en/stored-routines.html.

   Connector/J exposes stored procedure functionality through JDBC's
   CallableStatement interface.

Note

   Current versions of MySQL server do not return enough information
   for the JDBC driver to provide result set metadata for callable
   statements. This means that when using CallableStatement,
   ResultSetMetaData may return NULL.

   The following example shows a stored procedure that returns the
   value of inOutParam incremented by 1, and the string passed in via
   inputParam as a ResultSet:

   Example 5.3. Connector/J: Calling Stored Procedures
CREATE PROCEDURE demoSp(IN inputParam VARCHAR(255), \
                                        INOUT inOutParam INT)
BEGIN
    DECLARE z INT;
    SET z = inOutParam + 1;
    SET inOutParam = z;
    SELECT inputParam;
    SELECT CONCAT('zyxw', inputParam);
END

   To use the demoSp procedure with Connector/J, follow these steps:

    1. Prepare the callable statement by using
       Connection.prepareCall() .
       Notice that you have to use JDBC escape syntax, and that the
       parentheses surrounding the parameter placeholders are not
       optional:
       Example 5.4. Connector/J: Using Connection.prepareCall()
import java.sql.CallableStatement;
...
    //
    // Prepare a call to the stored procedure 'demoSp'
    // with two parameters
    //
    // Notice the use of JDBC-escape syntax ({call ...})
    //
    CallableStatement cStmt = conn.prepareCall("{call demoSp(?, ?)}")
;
    cStmt.setString(1, "abcdefg");

Note
       Connection.prepareCall() is an expensive method, due to the
       metadata retrieval that the driver performs to support output
       parameters. For performance reasons, you should try to
       minimize unnecessary calls to Connection.prepareCall() by
       reusing CallableStatement instances in your code.

    2. Register the output parameters (if any exist)
       To retrieve the values of output parameters (parameters
       specified as OUT or INOUT when you created the stored
       procedure), JDBC requires that they be specified before
       statement execution using the various
       registerOutputParameter() methods in the CallableStatement
       interface:
       Example 5.5. Connector/J: Registering output parameters
import java.sql.Types;
...
//
// Connector/J supports both named and indexed
// output parameters. You can register output
// parameters using either method, as well
// as retrieve output parameters using either
// method, regardless of what method was
// used to register them.
//
// The following examples show how to use
// the various methods of registering
// output parameters (you should of course
// use only one registration per parameter).
//
//
// Registers the second parameter as output, and
// uses the type 'INTEGER' for values returned from
// getObject()
//
cStmt.registerOutParameter(2, Types.INTEGER);
//
// Registers the named parameter 'inOutParam', and
// uses the type 'INTEGER' for values returned from
// getObject()
//
cStmt.registerOutParameter("inOutParam", Types.INTEGER);
...

    3. Set the input parameters (if any exist)
       Input and in/out parameters are set as for PreparedStatement
       objects. However, CallableStatement also supports setting
       parameters by name:
       Example 5.6. Connector/J: Setting CallableStatement input
       parameters
...
    //
    // Set a parameter by index
    //
    cStmt.setString(1, "abcdefg");
    //
    // Alternatively, set a parameter using
    // the parameter name
    //
    cStmt.setString("inputParameter", "abcdefg");
    //
    // Set the 'in/out' parameter using an index
    //
    cStmt.setInt(2, 1);
    //
    // Alternatively, set the 'in/out' parameter
    // by name
    //
    cStmt.setInt("inOutParam", 1);
...

    4. Execute the CallableStatement, and retrieve any result sets or
       output parameters.
       Although CallableStatement supports calling any of the
       Statement execute methods (executeUpdate(), executeQuery() or
       execute()), the most flexible method to call is execute(), as
       you do not need to know ahead of time if the stored procedure
       returns result sets:
       Example 5.7. Connector/J: Retrieving results and output
       parameter values
...
    boolean hadResults = cStmt.execute();
    //
    // Process all returned result sets
    //
    while (hadResults) {
        ResultSet rs = cStmt.getResultSet();
        // process result set
        ...
        hadResults = cStmt.getMoreResults();
    }
    //
    // Retrieve output parameters
    //
    // Connector/J supports both index-based and
    // name-based retrieval
    //
    int outputValue = cStmt.getInt(2); // index-based
    outputValue = cStmt.getInt("inOutParam"); // name-based
...

5.1.4. Retrieving AUTO_INCREMENT Column Values

   Before version 3.0 of the JDBC API, there was no standard way of
   retrieving key values from databases that supported auto increment
   or identity columns. With older JDBC drivers for MySQL, you could
   always use a MySQL-specific method on the Statement interface, or
   issue the query SELECT LAST_INSERT_ID() after issuing an INSERT
   (http://dev.mysql.com/doc/refman/5.0/en/insert.html) to a table
   that had an AUTO_INCREMENT key. Using the MySQL-specific method
   call isn't portable, and issuing a SELECT
   (http://dev.mysql.com/doc/refman/5.0/en/select.html) to get the
   AUTO_INCREMENT key's value requires another round-trip to the
   database, which isn't as efficient as possible. The following code
   snippets demonstrate the three different ways to retrieve
   AUTO_INCREMENT values. First, we demonstrate the use of the new
   JDBC-3.0 method getGeneratedKeys() which is now the preferred
   method to use if you need to retrieve AUTO_INCREMENT keys and have
   access to JDBC-3.0. The second example shows how you can retrieve
   the same value using a standard SELECT LAST_INSERT_ID() query. The
   final example shows how updatable result sets can retrieve the
   AUTO_INCREMENT value when using the insertRow() method.

   Example 5.8. Connector/J: Retrieving AUTO_INCREMENT column values
   using Statement.getGeneratedKeys()
   Statement stmt = null;
   ResultSet rs = null;
   try {
    //
    // Create a Statement instance that we can use for
    // 'normal' result sets assuming you have a
    // Connection 'conn' to a MySQL database already
    // available
    stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY,
                                java.sql.ResultSet.CONCUR_UPDATABLE);
    //
    // Issue the DDL queries for the table for this example
    //
    stmt.executeUpdate("DROP TABLE IF EXISTS autoIncTutorial");
    stmt.executeUpdate(
            "CREATE TABLE autoIncTutorial ("

            + "priKey INT NOT NULL AUTO_INCREMENT, "

            + "dataField VARCHAR(64), PRIMARY KEY (priKey))");
    //
    // Insert one row that will generate an AUTO INCREMENT
    // key in the 'priKey' field
    //
    stmt.executeUpdate(
            "INSERT INTO autoIncTutorial (dataField) "

            + "values ('Can I Get the Auto Increment Field?')",
            Statement.RETURN_GENERATED_KEYS);
    //
    // Example of using Statement.getGeneratedKeys()
    // to retrieve the value of an auto-increment
    // value
    //
    int autoIncKeyFromApi = -1;
    rs = stmt.getGeneratedKeys();
    if (rs.next()) {
        autoIncKeyFromApi = rs.getInt(1);
    } else {
        // throw an exception from here
    }
    rs.close();
    rs = null;
    System.out.println("Key returned from getGeneratedKeys():"

        + autoIncKeyFromApi);
} finally {
    if (rs != null) {
        try {
            rs.close();
        } catch (SQLException ex) {
            // ignore
        }
    }
    if (stmt != null) {
        try {
            stmt.close();
        } catch (SQLException ex) {
            // ignore
        }
    }
}

   Example 5.9. Connector/J: Retrieving AUTO_INCREMENT column values
   using SELECT LAST_INSERT_ID()
   Statement stmt = null;
   ResultSet rs = null;
   try {
    //
    // Create a Statement instance that we can use for
    // 'normal' result sets.
    stmt = conn.createStatement();
    //
    // Issue the DDL queries for the table for this example
    //
    stmt.executeUpdate("DROP TABLE IF EXISTS autoIncTutorial");
    stmt.executeUpdate(
            "CREATE TABLE autoIncTutorial ("

            + "priKey INT NOT NULL AUTO_INCREMENT, "

            + "dataField VARCHAR(64), PRIMARY KEY (priKey))");
    //
    // Insert one row that will generate an AUTO INCREMENT
    // key in the 'priKey' field
    //
    stmt.executeUpdate(
            "INSERT INTO autoIncTutorial (dataField) "

            + "values ('Can I Get the Auto Increment Field?')");
    //
    // Use the MySQL LAST_INSERT_ID()
    // function to do the same thing as getGeneratedKeys()
    //
    int autoIncKeyFromFunc = -1;
    rs = stmt.executeQuery("SELECT LAST_INSERT_ID()");
    if (rs.next()) {
        autoIncKeyFromFunc = rs.getInt(1);
    } else {
        // throw an exception from here
    }
    rs.close();
    System.out.println("Key returned from " +
                       "'SELECT LAST_INSERT_ID()': " +
                       autoIncKeyFromFunc);
} finally {
    if (rs != null) {
        try {
            rs.close();
        } catch (SQLException ex) {
            // ignore
        }
    }
    if (stmt != null) {
        try {
            stmt.close();
        } catch (SQLException ex) {
            // ignore
        }
    }
}


   Example 5.10. Connector/J: Retrieving AUTO_INCREMENT column values
   in Updatable ResultSets
   Statement stmt = null;
   ResultSet rs = null;
   try {
    //
    // Create a Statement instance that we can use for
    // 'normal' result sets as well as an 'updatable'
    // one, assuming you have a Connection 'conn' to
    // a MySQL database already available
    //
    stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY,
                                java.sql.ResultSet.CONCUR_UPDATABLE);
    //
    // Issue the DDL queries for the table for this example
    //
    stmt.executeUpdate("DROP TABLE IF EXISTS autoIncTutorial");
    stmt.executeUpdate(
            "CREATE TABLE autoIncTutorial ("

            + "priKey INT NOT NULL AUTO_INCREMENT, "

            + "dataField VARCHAR(64), PRIMARY KEY (priKey))");
    //
    // Example of retrieving an AUTO INCREMENT key
    // from an updatable result set
    //
    rs = stmt.executeQuery("SELECT priKey, dataField "

       + "FROM autoIncTutorial");
    rs.moveToInsertRow();
    rs.updateString("dataField", "AUTO INCREMENT here?");
    rs.insertRow();
    //
    // the driver adds rows at the end
    //
    rs.last();
    //
    // We should now be on the row we just inserted
    //
    int autoIncKeyFromRS = rs.getInt("priKey");
    rs.close();
    rs = null;
    System.out.println("Key returned for inserted row: "

        + autoIncKeyFromRS);
} finally {
    if (rs != null) {
        try {
            rs.close();
        } catch (SQLException ex) {
            // ignore
        }
    }
    if (stmt != null) {
        try {
            stmt.close();
        } catch (SQLException ex) {
            // ignore
        }
    }
}


   When you run the preceding example code, you should get the
   following output: Key returned from getGeneratedKeys(): 1 Key
   returned from SELECT LAST_INSERT_ID(): 1 Key returned for inserted
   row: 2 You should be aware, that at times, it can be tricky to use
   the SELECT LAST_INSERT_ID() query, as that function's value is
   scoped to a connection. So, if some other query happens on the
   same connection, the value will be overwritten. On the other hand,
   the getGeneratedKeys() method is scoped by the Statement instance,
   so it can be used even if other queries happen on the same
   connection, but not on the same Statement instance.

5.2. Using Connector/J with J2EE and Other Java Frameworks

   This section describes how to use Connector/J in several contexts.

5.2.1. General J2EE Concepts

   This section provides general background on J2EE concepts that
   pertain to use of Connector/J.

5.2.1.1. Understanding Connection Pooling

   Connection pooling is a technique of creating and managing a pool
   of connections that are ready for use by any thread that needs
   them.

   This technique of pooling connections is based on the fact that
   most applications only need a thread to have access to a JDBC
   connection when they are actively processing a transaction, which
   usually take only milliseconds to complete. When not processing a
   transaction, the connection would otherwise sit idle. Instead,
   connection pooling allows the idle connection to be used by some
   other thread to do useful work.

   In practice, when a thread needs to do work against a MySQL or
   other database with JDBC, it requests a connection from the pool.
   When the thread is finished using the connection, it returns it to
   the pool, so that it may be used by any other threads that want to
   use it.

   When the connection is loaned out from the pool, it is used
   exclusively by the thread that requested it. From a programming
   point of view, it is the same as if your thread called
   DriverManager.getConnection() every time it needed a JDBC
   connection, however with connection pooling, your thread may end
   up using either a new, or already-existing connection.

   Connection pooling can greatly increase the performance of your
   Java application, while reducing overall resource usage. The main
   benefits to connection pooling are:

     * Reduced connection creation time
       Although this is not usually an issue with the quick
       connection setup that MySQL offers compared to other
       databases, creating new JDBC connections still incurs
       networking and JDBC driver overhead that will be avoided if
       connections are recycled.

     * Simplified programming model
       When using connection pooling, each individual thread can act
       as though it has created its own JDBC connection, allowing you
       to use straight-forward JDBC programming techniques.

     * Controlled resource usage
       If you do not use connection pooling, and instead create a new
       connection every time a thread needs one, your application's
       resource usage can be quite wasteful and lead to unpredictable
       behavior under load.

   Remember that each connection to MySQL has overhead (memory, CPU,
   context switches, and so forth) on both the client and server
   side. Every connection limits how many resources there are
   available to your application as well as the MySQL server. Many of
   these resources will be used whether or not the connection is
   actually doing any useful work!

   Connection pools can be tuned to maximize performance, while
   keeping resource utilization below the point where your
   application will start to fail rather than just run slower.

   Luckily, Sun has standardized the concept of connection pooling in
   JDBC through the JDBC-2.0 Optional interfaces, and all major
   application servers have implementations of these APIs that work
   fine with MySQL Connector/J.

   Generally, you configure a connection pool in your application
   server configuration files, and access it via the Java Naming and
   Directory Interface (JNDI). The following code shows how you might
   use a connection pool from an application deployed in a J2EE
   application server:

   Example 5.11. Connector/J: Using a connection pool with a J2EE
   application server
import java.sql.Connection;
import java.sql.SQLException;
import java.sql.Statement;
import javax.naming.InitialContext;
import javax.sql.DataSource;
public class MyServletJspOrEjb {
    public void doSomething() throws Exception {
        /*

         * Create a JNDI Initial context to be able to

         *  lookup  the DataSource
         *

         * In production-level code, this should be cached as

         * an instance or static variable, as it can

         * be quite expensive to create a JNDI context.
         *

         * Note: This code only works when you are using servlets

         * or EJBs in a J2EE application server. If you are

         * using connection pooling in standalone Java code, you

         * will have to create/configure datasources using whatever

         * mechanisms your particular connection pooling library

         * provides.
         */
        InitialContext ctx = new InitialContext();
         /*

          * Lookup the DataSource, which will be backed by a pool

          * that the application server provides. DataSource instance
s

          * are also a good candidate for caching as an instance

          * variable, as JNDI lookups can be expensive as well.
          */
        DataSource ds =
          (DataSource)ctx.lookup("java:comp/env/jdbc/MySQLDB");
        /*

         * The following code is what would actually be in your

         * Servlet, JSP or EJB 'service' method...where you need

         * to work with a JDBC connection.
         */
        Connection conn = null;
        Statement stmt = null;
        try {
            conn = ds.getConnection();
            /*

             * Now, use normal JDBC programming to work with

             * MySQL, making sure to close each resource when you're

             * finished with it, which allows the connection pool

             * resources to be recovered as quickly as possible
             */
            stmt = conn.createStatement();
            stmt.execute("SOME SQL QUERY");
            stmt.close();
            stmt = null;
            conn.close();
            conn = null;
        } finally {
            /*

             * close any jdbc instances here that weren't

             * explicitly closed during normal code path, so

             * that we don't 'leak' resources...
             */
            if (stmt != null) {
                try {
                    stmt.close();
                } catch (sqlexception sqlex) {
                    // ignore -- as we can't do anything about it her
e
                }
                stmt = null;
            }
            if (conn != null) {
                try {
                    conn.close();
                } catch (sqlexception sqlex) {
                    // ignore -- as we can't do anything about it her
e
                }
                conn = null;
            }
        }
    }
}

   As shown in the example above, after obtaining the JNDI
   InitialContext, and looking up the DataSource, the rest of the
   code should look familiar to anyone who has done JDBC programming
   in the past.

   The most important thing to remember when using connection pooling
   is to make sure that no matter what happens in your code
   (exceptions, flow-of-control, and so forth), connections, and
   anything created by them (such as statements or result sets) are
   closed, so that they may be re-used, otherwise they will be
   stranded, which in the best case means that the MySQL server
   resources they represent (such as buffers, locks, or sockets) may
   be tied up for some time, or worst case, may be tied up forever.

   What Is the Best Size for my Connection Pool?

   As with all other configuration rules-of-thumb, the answer is: it
   depends. Although the optimal size depends on anticipated load and
   average database transaction time, the optimum connection pool
   size is smaller than you might expect. If you take Sun's Java
   Petstore blueprint application for example, a connection pool of
   15-20 connections can serve a relatively moderate load (600
   concurrent users) using MySQL and Tomcat with response times that
   are acceptable.

   To correctly size a connection pool for your application, you
   should create load test scripts with tools such as Apache JMeter
   or The Grinder, and load test your application.

   An easy way to determine a starting point is to configure your
   connection pool's maximum number of connections to be unbounded,
   run a load test, and measure the largest amount of concurrently
   used connections. You can then work backward from there to
   determine what values of minimum and maximum pooled connections
   give the best performance for your particular application.

5.2.2. Using Connector/J with Tomcat

   The following instructions are based on the instructions for
   Tomcat-5.x, available at
   http://tomcat.apache.org/tomcat-5.5-doc/jndi-datasource-examples-h
   owto.html which is current at the time this document was written.

   First, install the .jar file that comes with Connector/J in
   $CATALINA_HOME/common/lib so that it is available to all
   applications installed in the container.

   Next, Configure the JNDI DataSource by adding a declaration
   resource to $CATALINA_HOME/conf/server.xml in the context that
   defines your web application:
<Context ....>
  ...
  <Resource name="jdbc/MySQLDB"
               auth="Container"
               type="javax.sql.DataSource"/>
  <!-- The name you used above, must match _exactly_ here!
       The connection pool will be bound into JNDI with the name
       "java:/comp/env/jdbc/MySQLDB"
  -->
  <ResourceParams name="jdbc/MySQLDB">
    <parameter>
      <name>factory</name>
      <value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
    </parameter>
    <!-- Don't set this any higher than max_connections on your
         MySQL server, usually this should be a 10 or a few 10's
         of connections, not hundreds or thousands -->
    <parameter>
      <name>maxActive</name>
      <value>10</value>
    </parameter>
    <!-- You don't want to many idle connections hanging around
         if you can avoid it, only enough to soak up a spike in
         the load -->
    <parameter>
      <name>maxIdle</name>
      <value>5</value>
    </parameter>
    <!-- Don't use autoReconnect=true, it's going away eventually
         and it's a crutch for older connection pools that couldn't
         test connections. You need to decide whether your applicatio
n
         is supposed to deal with SQLExceptions (hint, it should), an
d
         how much of a performance penalty you're willing to pay
         to ensure 'freshness' of the connection -->
    <parameter>
      <name>validationQuery</name>
      <value>SELECT 1</value>
    </parameter>
   <!-- The most conservative approach is to test connections
        before they're given to your application. For most applicatio
ns
        this is okay, the query used above is very small and takes
        no real server resources to process, other than the time used
        to traverse the network.
        If you have a high-load application you'll need to rely on
        something else. -->
    <parameter>
      <name>testOnBorrow</name>
      <value>true</value>
    </parameter>
   <!-- Otherwise, or in addition to testOnBorrow, you can test
        while connections are sitting idle -->
    <parameter>
      <name>testWhileIdle</name>
      <value>true</value>
    </parameter>
    <!-- You have to set this value, otherwise even though
         you've asked connections to be tested while idle,
         the idle evicter thread will never run -->
    <parameter>
      <name>timeBetweenEvictionRunsMillis</name>
      <value>10000</value>
    </parameter>
    <!-- Don't allow connections to hang out idle too long,
         never longer than what wait_timeout is set to on the
         server...A few minutes or even fraction of a minute
         is sometimes okay here, it depends on your application
         and how much spikey load it will see -->
    <parameter>
      <name>minEvictableIdleTimeMillis</name>
      <value>60000</value>
    </parameter>
    <!-- Username and password used when connecting to MySQL -->
    <parameter>
     <name>username</name>
     <value>someuser</value>
    </parameter>
    <parameter>
     <name>password</name>
     <value>somepass</value>
    </parameter>
    <!-- Class name for the Connector/J driver -->
    <parameter>
       <name>driverClassName</name>
       <value>com.mysql.jdbc.Driver</value>
    </parameter>
    <!-- The JDBC connection url for connecting to MySQL, notice
         that if you want to pass any other MySQL-specific parameters
         you should pass them here in the URL, setting them using the
         parameter tags above will have no effect, you will also
         need to use &amp; to separate parameter values as the
         ampersand is a reserved character in XML -->
    <parameter>
      <name>url</name>
      <value>jdbc:mysql://localhost:3306/test</value>
    </parameter>
  </ResourceParams>
</Context>

   In general, you should follow the installation instructions that
   come with your version of Tomcat, as the way you configure
   datasources in Tomcat changes from time-to-time, and unfortunately
   if you use the wrong syntax in your XML file, you will most likely
   end up with an exception similar to the following:
Error: java.sql.SQLException: Cannot load JDBC driver class 'null ' S
QL
state: null

5.2.3. Using Connector/J with JBoss

   These instructions cover JBoss-4.x. To make the JDBC driver
   classes available to the application server, copy the .jar file
   that comes with Connector/J to the lib directory for your server
   configuration (which is usually called default). Then, in the same
   configuration directory, in the subdirectory named deploy, create
   a datasource configuration file that ends with "-ds.xml", which
   tells JBoss to deploy this file as a JDBC Datasource. The file
   should have the following contents:
<datasources>
    <local-tx-datasource>
        <!-- This connection pool will be bound into JNDI with the na
me
             "java:/MySQLDB" -->
        <jndi-name>MySQLDB</jndi-name>
        <connection-url>jdbc:mysql://localhost:3306/dbname</connectio
n-url>
        <driver-class>com.mysql.jdbc.Driver</driver-class>
        <user-name>user</user-name>
        <password>pass</password>
        <min-pool-size>5</min-pool-size>
        <!-- Don't set this any higher than max_connections on your
         MySQL server, usually this should be a 10 or a few 10's
         of connections, not hundreds or thousands -->
        <max-pool-size>20</max-pool-size>
        <!-- Don't allow connections to hang out idle too long,
         never longer than what wait_timeout is set to on the
         server...A few minutes is usually okay here,
         it depends on your application
         and how much spikey load it will see -->
        <idle-timeout-minutes>5</idle-timeout-minutes>
        <!-- If you're using Connector/J 3.1.8 or newer, you can use
             our implementation of these to increase the robustness
             of the connection pool. -->
        <exception-sorter-class-name>
  com.mysql.jdbc.integration.jboss.ExtendedMysqlExceptionSorter
        </exception-sorter-class-name>
        <valid-connection-checker-class-name>
  com.mysql.jdbc.integration.jboss.MysqlValidConnectionChecker
        </valid-connection-checker-class-name>
    </local-tx-datasource>
</datasources>

5.2.4. Using Connector/J with Spring

   The Spring Framework is a Java-based application framework
   designed for assisting in application design by providing a way to
   configure components. The technique used by Spring is a well known
   design pattern called Dependency Injection (see Inversion of
   Control Containers and the Dependency Injection pattern
   (http://www.martinfowler.com/articles/injection.html)). This
   article will focus on Java-oriented access to MySQL databases with
   Spring 2.0. For those wondering, there is a .NET port of Spring
   appropriately named Spring.NET.

   Spring is not only a system for configuring components, but also
   includes support for aspect oriented programming (AOP). This is
   one of the main benefits and the foundation for Spring's resource
   and transaction management. Spring also provides utilities for
   integrating resource management with JDBC and Hibernate.

   For the examples in this section the MySQL world sample database
   will be used. The first task is to set up a MySQL data source
   through Spring. Components within Spring use the "bean"
   terminology. For example, to configure a connection to a MySQL
   server supporting the world sample database you might use:
<util:map id="dbProps">
    <entry key="db.driver" value="com.mysql.jdbc.Driver"/>
    <entry key="db.jdbcurl" value="jdbc:mysql://localhost/world"/>
    <entry key="db.username" value="myuser"/>
    <entry key="db.password" value="mypass"/>
</util:map>



   In the above example we are assigning values to properties that
   will be used in the configuration. For the datasource
   configuration:
<bean id="dataSource"
       class="org.springframework.jdbc.datasource.DriverManagerDataSo
urce">
    <property name="driverClassName" value="${db.driver}"/>
    <property name="url" value="${db.jdbcurl}"/>
    <property name="username" value="${db.username}"/>
    <property name="password" value="${db.password}"/>
</bean>


   The placeholders are used to provide values for properties of this
   bean. This means that you can specify all the properties of the
   configuration in one place instead of entering the values for each
   property on each bean. We do, however, need one more bean to pull
   this all together. The last bean is responsible for actually
   replacing the placeholders with the property values.
<bean
 class="org.springframework.beans.factory.config.PropertyPlaceholderC
onfigurer">
    <property name="properties" ref="dbProps"/>
</bean>


   Now that we have our MySQL data source configured and ready to go,
   we write some Java code to access it. The example below will
   retrieve three random cities and their corresponding country using
   the data source we configured with Spring.
// Create a new application context. this processes the Spring config
ApplicationContext ctx =
    new ClassPathXmlApplicationContext("ex1appContext.xml");
// Retrieve the data source from the application context
    DataSource ds = (DataSource) ctx.getBean("dataSource");
// Open a database connection using Spring's DataSourceUtils
Connection c = DataSourceUtils.getConnection(ds);
try {
    // retrieve a list of three random cities
    PreparedStatement ps = c.prepareStatement(
        "select City.Name as 'City', Country.Name as 'Country' " +
        "from City inner join Country on City.CountryCode = Country.C
ode " +
        "order by rand() limit 3");
    ResultSet rs = ps.executeQuery();
    while(rs.next()) {
        String city = rs.getString("City");
        String country = rs.getString("Country");
        System.out.printf("The city %s is in %s%n", city, country);
    }
} catch (SQLException ex) {
    // something has failed and we print a stack trace to analyse the
 error
    ex.printStackTrace();
    // ignore failure closing connection
    try { c.close(); } catch (SQLException e) { }
} finally {
    // properly release our connection
    DataSourceUtils.releaseConnection(c, ds);
}

   This is very similar to normal JDBC access to MySQL with the main
   difference being that we are using DataSourceUtils instead of the
   DriverManager to create the connection.

   While it may seem like a small difference, the implications are
   somewhat far reaching. Spring manages this resource in a way
   similar to a container managed data source in a J2EE application
   server. When a connection is opened, it can be subsequently
   accessed in other parts of the code if it is synchronized with a
   transaction. This makes it possible to treat different parts of
   your application as transactional instead of passing around a
   database connection.

5.2.4.1. Using JdbcTemplate

   Spring makes extensive use of the Template method design pattern
   (see Template Method Pattern
   (http://en.wikipedia.org/wiki/Template_method_pattern)). Our
   immediate focus will be on the JdbcTemplate and related classes,
   specifically NamedParameterJdbcTemplate. The template classes
   handle obtaining and releasing a connection for data access when
   one is needed.

   The next example shows how to use NamedParameterJdbcTemplate
   inside of a DAO (Data Access Object) class to retrieve a random
   city given a country code.
public class Ex2JdbcDao {
     /**

     * Data source reference which will be provided by Spring.
     */
     private DataSource dataSource;
     /**

     * Our query to find a random city given a country code. Notice

     * the ":country" parameter towards the end. This is called a

     * named parameter.
     */
     private String queryString = "select Name from City " +
        "where CountryCode = :country order by rand() limit 1";
     /**

     * Retrieve a random city using Spring JDBC access classes.
     */
     public String getRandomCityByCountryCode(String cntryCode) {
         // A template that allows using queries with named parameter
s
         NamedParameterJdbcTemplate template =
         new NamedParameterJdbcTemplate(dataSource);
         // A java.util.Map is used to provide values for the paramet
ers
         Map params = new HashMap();
         params.put("country", cntryCode);
         // We query for an Object and specify what class we are expe
cting
         return (String)template.queryForObject(queryString, params,
String.class);
     }
    /**

    * A JavaBean setter-style method to allow Spring to inject the da
ta source.

    * @param dataSource
    */
    public void setDataSource(DataSource dataSource) {
        this.dataSource = dataSource;
    }
}


   The focus in the above code is on the getRandomCityByCountryCode()
   method. We pass a country code and use the
   NamedParameterJdbcTemplate to query for a city. The country code
   is placed in a Map with the key "country", which is the parameter
   is named in the SQL query.

   To access this code, you need to configure it with Spring by
   providing a reference to the data source.
<bean id="dao" class="code.Ex2JdbcDao">
    <property name="dataSource" ref="dataSource"/>
</bean>

   At this point, we can just grab a reference to the DAO from Spring
   and call getRandomCityByCountryCode().
// Create the application context
    ApplicationContext ctx =
    new ClassPathXmlApplicationContext("ex2appContext.xml");
    // Obtain a reference to our DAO
    Ex2JdbcDao dao = (Ex2JdbcDao) ctx.getBean("dao");
    String countryCode = "USA";
    // Find a few random cities in the US
    for(int i = 0; i < 4; ++i)
        System.out.printf("A random city in %s is %s%n", countryCode,
            dao.getRandomCityByCountryCode(countryCode));

   This example shows how to use Spring's JDBC classes to completely
   abstract away the use of traditional JDBC classes including
   Connection and PreparedStatement.

5.2.4.2. Transactional JDBC Access

   You might be wondering how we can add transactions into our code
   if we do not deal directly with the JDBC classes. Spring provides
   a transaction management package that not only replaces JDBC
   transaction management, but also allows declarative transaction
   management (configuration instead of code).

   In order to use transactional database access, we will need to
   change the storage engine of the tables in the world database. The
   downloaded script explicitly creates MyISAM tables which do not
   support transactional semantics. The InnoDB storage engine does
   support transactions and this is what we will be using. We can
   change the storage engine with the following statements.
ALTER TABLE City ENGINE=InnoDB;
ALTER TABLE Country ENGINE=InnoDB;
ALTER TABLE CountryLanguage ENGINE=InnoDB;

   A good programming practice emphasized by Spring is separating
   interfaces and implementations. What this means is that we can
   create a Java interface and only use the operations on this
   interface without any internal knowledge of what the actual
   implementation is. We will let Spring manage the implementation
   and with this it will manage the transactions for our
   implementation.

   First you create a simple interface:
public interface Ex3Dao {
    Integer createCity(String name, String countryCode,
    String district, Integer population);
}

   This interface contains one method that will create a new city
   record in the database and return the id of the new record. Next
   you need to create an implementation of this interface.
public class Ex3DaoImpl implements Ex3Dao {
    protected DataSource dataSource;
    protected SqlUpdate updateQuery;
    protected SqlFunction idQuery;
    public Integer createCity(String name, String countryCode,
        String district, Integer population) {
            updateQuery.update(new Object[] { name, countryCode,
                   district, population });
            return getLastId();
        }
    protected Integer getLastId() {
        return idQuery.run();
    }
}

   You can see that we only operate on abstract query objects here
   and do not deal directly with the JDBC API. Also, this is the
   complete implementation. All of our transaction management will be
   dealt with in the configuration. To get the configuration started,
   we need to create the DAO.
<bean id="dao" class="code.Ex3DaoImpl">
    <property name="dataSource" ref="dataSource"/>
    <property name="updateQuery">...</property>
    <property name="idQuery">...</property>
</bean>

   Now you need to set up the transaction configuration. The first
   thing you must do is create transaction manager to manage the data
   source and a specification of what transaction properties are
   required for the dao methods.
<bean id="transactionManager"
  class="org.springframework.jdbc.datasource.DataSourceTransactionMan
ager">
    <property name="dataSource" ref="dataSource"/>
</bean>
<tx:advice id="txAdvice" transaction-manager="transactionManager">
    <tx:attributes>
        <tx:method name="*"/>
    </tx:attributes>
</tx:advice>

   The preceding code creates a transaction manager that handles
   transactions for the data source provided to it. The txAdvice uses
   this transaction manager and the attributes specify to create a
   transaction for all methods. Finally you need to apply this advice
   with an AOP pointcut.
<aop:config>
    <aop:pointcut id="daoMethods"
        expression="execution(* code.Ex3Dao.*(..))"/>
     <aop:advisor advice-ref="txAdvice" pointcut-ref="daoMethods"/>
</aop:config>

   This basically says that all methods called on the Ex3Dao
   interface will be wrapped in a transaction. To make use of this,
   you only have to retrieve the dao from the application context and
   call a method on the dao instance.
Ex3Dao dao = (Ex3Dao) ctx.getBean("dao");
Integer id = dao.createCity(name,  countryCode, district, pop);

   We can verify from this that there is no transaction management
   happening in our Java code and it is all configured with Spring.
   This is a very powerful notion and regarded as one of the most
   beneficial features of Spring.

5.2.4.3. Connection Pooling

   In many sitations, such as web applications, there will be a large
   number of small database transactions. When this is the case, it
   usually makes sense to create a pool of database connections
   available for web requests as needed. Although MySQL does not
   spawn an extra process when a connection is made, there is still a
   small amount of overhead to create and set up the connection.
   Pooling of connections also alleviates problems such as collecting
   large amounts of sockets in the TIME_WAIT state.

   Setting up pooling of MySQL connections with Spring is as simple
   as changing the data source configuration in the application
   context. There are a number of configurations that we can use. The
   first example is based on the Jakarta Commons DBCP library
   (http://jakarta.apache.org/commons/dbcp/). The example below
   replaces the source configuration that was based on
   DriverManagerDataSource with DBCP's BasicDataSource.
<bean id="dataSource" destroy-method="close"
  class="org.apache.commons.dbcp.BasicDataSource">
    <property name="driverClassName" value="${db.driver}"/>
    <property name="url" value="${db.jdbcurl}"/>
    <property name="username" value="${db.username}"/>
    <property name="password" value="${db.password}"/>
    <property name="initialSize" value="3"/>
</bean>

   The configuration of the two solutions is very similar. The
   difference is that DBCP will pool connections to the database
   instead of creating a new connection every time one is requested.
   We have also set a parameter here called initialSize. This tells
   DBCP that we want three connections in the pool when it is
   created.

   Another way to configure connection pooling is to configure a data
   source in our J2EE application server. Using JBoss as an example,
   you can set up the MySQL connection pool by creating a file called
   mysql-local-ds.xml and placing it in the server/default/deploy
   directory in JBoss. Once we have this setup, we can use JNDI to
   look it up. With Spring, this lookup is very simple. The data
   source configuration looks like this.
<jee:jndi-lookup id="dataSource" jndi-name="java:MySQL_DS"/>

5.2.5. Using Connector/J with GlassFish

5.3. Common Problems and Solutions

   There are a few issues that seem to be commonly encountered often
   by users of MySQL Connector/J. This section deals with their
   symptoms, and their resolutions.

   Questions

     * 5.3.1: When I try to connect to the database with MySQL
       Connector/J, I get the following exception:
SQLException: Server configuration denies access to data source
SQLState: 08001
VendorError: 0
       What is going on? I can connect just fine with the MySQL
       command-line client.

     * 5.3.2: My application throws an SQLException 'No Suitable
       Driver'. Why is this happening?

     * 5.3.3: I'm trying to use MySQL Connector/J in an applet or
       application and I get an exception similar to:
SQLException: Cannot connect to MySQL server on host:3306.
Is there a MySQL server running on the machine/port you
are trying to connect to?
(java.security.AccessControlException)
SQLState: 08S01
VendorError: 0

     * 5.3.4: I have a servlet/application that works fine for a day,
       and then stops working overnight

     * 5.3.5: I'm trying to use JDBC-2.0 updatable result sets, and I
       get an exception saying my result set is not updatable.

     * 5.3.6: I cannot connect to the MySQL server using Connector/J,
       and I'm sure the connection paramters are correct.

     * 5.3.7: I am trying to connect to my MySQL server within my
       application, but I get the following error and stack trace:
java.net.SocketException
MESSAGE: Software caused connection abort: recv failed
STACKTRACE:
java.net.SocketException: Software caused connection abort: recv fail
ed
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(Unknown Source)
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1392)
at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:1414)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:625)
at com.mysql.jdbc.Connection.createNewIO(Connection.java:1926)
at com.mysql.jdbc.Connection.<init>(Connection.java:452)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.j
ava:411)

     * 5.3.8: My application is deployed through JBoss and I am using
       transactions to handle the statements on the MySQL database.
       Under heavy loads I am getting a error and stack trace, but
       these only occur after a fixed period of heavy activity.

     * 5.3.9: When using gcj an java.io.CharConversionException is
       raised when working with certain character sequences.

     * 5.3.10: Updating a table that contains a primary key that is
       either FLOAT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html) or
       compound primary key that uses FLOAT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       fails to update the table and raises an exception.

     * 5.3.11: You get an ER_NET_PACKET_TOO_LARGE
       (http://dev.mysql.com/doc/refman/5.0/en/error_er_net_packet_to
       o_large.html#error_er_net_packet_too_large) exception, even
       though the binary blob size you want to insert via JDBC is
       safely below the max_allowed_packet
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_max_allowed_packet) size.

   Questions and Answers

   5.3.1: When I try to connect to the database with MySQL
   Connector/J, I get the following exception: 
SQLException: Server configuration denies access to data source
SQLState: 08001
VendorError: 0

   What is going on? I can connect just fine with the MySQL
   command-line client. 

   MySQL Connector/J must use TCP/IP sockets to connect to MySQL, as
   Java does not support Unix Domain Sockets. Therefore, when MySQL
   Connector/J connects to MySQL, the security manager in MySQL
   server will use its grant tables to determine whether the
   connection should be allowed.

   You must add the necessary security credentials to the MySQL
   server for this to happen, using the GRANT
   (http://dev.mysql.com/doc/refman/5.0/en/grant.html) statement to
   your MySQL Server. See GRANT Syntax
   (http://dev.mysql.com/doc/refman/5.0/en/grant.html), for more
   information.

Note

   Testing your connectivity with the mysql command-line client will
   not work unless you add the --host
   (http://dev.mysql.com/doc/refman/5.0/en/mysql-description.html#opt
   ion_mysql_host) flag, and use something other than localhost for
   the host. The mysql command-line client will use Unix domain
   sockets if you use the special host name localhost. If you are
   testing connectivity to localhost, use 127.0.0.1 as the host name
   instead.

Warning

   Changing privileges and permissions improperly in MySQL can
   potentially cause your server installation to not have optimal
   security properties.

   5.3.2: My application throws an SQLException 'No Suitable Driver'.
   Why is this happening? 

   There are three possible causes for this error:

     * The Connector/J driver is not in your CLASSPATH, see Chapter
       2, "Connector/J Installation."

     * The format of your connection URL is incorrect, or you are
       referencing the wrong JDBC driver.

     * When using DriverManager, the jdbc.drivers system property has
       not been populated with the location of the Connector/J
       driver.

   5.3.3: I'm trying to use MySQL Connector/J in an applet or
   application and I get an exception similar to: 
SQLException: Cannot connect to MySQL server on host:3306.
Is there a MySQL server running on the machine/port you
are trying to connect to?
(java.security.AccessControlException)
SQLState: 08S01
VendorError: 0

   Either you're running an Applet, your MySQL server has been
   installed with the "--skip-networking" option set, or your MySQL
   server has a firewall sitting in front of it.

   Applets can only make network connections back to the machine that
   runs the web server that served the .class files for the applet.
   This means that MySQL must run on the same machine (or you must
   have some sort of port re-direction) for this to work. This also
   means that you will not be able to test applets from your local
   file system, you must always deploy them to a web server.

   MySQL Connector/J can only communicate with MySQL using TCP/IP, as
   Java does not support Unix domain sockets. TCP/IP communication
   with MySQL might be affected if MySQL was started with the
   "--skip-networking" flag, or if it is firewalled.

   If MySQL has been started with the "--skip-networking" option set
   (the Debian Linux package of MySQL server does this for example),
   you need to comment it out in the file /etc/mysql/my.cnf or
   /etc/my.cnf. Of course your my.cnf file might also exist in the
   data directory of your MySQL server, or anywhere else (depending
   on how MySQL was compiled for your system). Binaries created by us
   always look in /etc/my.cnf and [datadir]/my.cnf. If your MySQL
   server has been firewalled, you will need to have the firewall
   configured to allow TCP/IP connections from the host where your
   Java code is running to the MySQL server on the port that MySQL is
   listening to (by default, 3306).

   5.3.4: I have a servlet/application that works fine for a day, and
   then stops working overnight 

   MySQL closes connections after 8 hours of inactivity. You either
   need to use a connection pool that handles stale connections or
   use the "autoReconnect" parameter (see Section 4.1,
   "Driver/Datasource Class Names, URL Syntax and Configuration
   Properties for Connector/J").

   Also, you should be catching SQLExceptions in your application and
   dealing with them, rather than propagating them all the way until
   your application exits, this is just good programming practice.
   MySQL Connector/J will set the SQLState (see
   java.sql.SQLException.getSQLState() in your APIDOCS) to "08S01"
   when it encounters network-connectivity issues during the
   processing of a query. Your application code should then attempt
   to re-connect to MySQL at this point.

   The following (simplistic) example shows what code that can handle
   these exceptions might look like:

   Example 5.12. Connector/J: Example of transaction with retry logic
public void doBusinessOp() throws SQLException {
    Connection conn = null;
    Statement stmt = null;
    ResultSet rs = null;
    //
    // How many times do you want to retry the transaction
    // (or at least _getting_ a connection)?
    //
    int retryCount = 5;
    boolean transactionCompleted = false;
    do {
        try {
            conn = getConnection(); // assume getting this from a
                                    // javax.sql.DataSource, or the
                                    // java.sql.DriverManager
            conn.setAutoCommit(false);
            //
            // Okay, at this point, the 'retry-ability' of the
            // transaction really depends on your application logic,
            // whether or not you're using autocommit (in this case
            // not), and whether you're using transacational storage
            // engines
            //
            // For this example, we'll assume that it's _not_ safe
            // to retry the entire transaction, so we set retry
            // count to 0 at this point
            //
            // If you were using exclusively transaction-safe tables,
            // or your application could recover from a connection go
ing
            // bad in the middle of an operation, then you would not
            // touch 'retryCount' here, and just let the loop repeat
            // until retryCount == 0.
            //
            retryCount = 0;
            stmt = conn.createStatement();
            String query = "SELECT foo FROM bar ORDER BY baz";
            rs = stmt.executeQuery(query);
            while (rs.next()) {
            }
            rs.close();
            rs = null;
            stmt.close();
            stmt = null;
            conn.commit();
            conn.close();
            conn = null;
            transactionCompleted = true;
        } catch (SQLException sqlEx) {
            //
            // The two SQL states that are 'retry-able' are 08S01
            // for a communications error, and 40001 for deadlock.
            //
            // Only retry if the error was due to a stale connection,
            // communications problem or deadlock
            //
            String sqlState = sqlEx.getSQLState();
            if ("08S01".equals(sqlState) || "40001".equals(sqlState))
 {
                retryCount--;
            } else {
                retryCount = 0;
            }
        } finally {
            if (rs != null) {
                try {
                    rs.close();
                } catch (SQLException sqlEx) {
                    // You'd probably want to log this . . .
                }
            }
            if (stmt != null) {
                try {
                    stmt.close();
                } catch (SQLException sqlEx) {
                    // You'd probably want to log this as well . . .
                }
            }
            if (conn != null) {
                try {
                    //
                    // If we got here, and conn is not null, the
                    // transaction should be rolled back, as not
                    // all work has been done
                    try {
                        conn.rollback();
                    } finally {
                        conn.close();
                    }
                } catch (SQLException sqlEx) {
                    //
                    // If we got an exception here, something
                    // pretty serious is going on, so we better
                    // pass it up the stack, rather than just
                    // logging it. . .
                    throw sqlEx;
                }
            }
        }
    } while (!transactionCompleted && (retryCount > 0));
}

Note

   Use of the autoReconnect option is not recommended because there
   is no safe method of reconnecting to the MySQL server without
   risking some corruption of the connection state or database state
   information. Instead, you should use a connection pool which will
   enable your application to connect to the MySQL server using an
   available connection from the pool. The autoReconnect facility is
   deprecated, and may be removed in a future release.

   5.3.5: I'm trying to use JDBC-2.0 updatable result sets, and I get
   an exception saying my result set is not updatable. 

   Because MySQL does not have row identifiers, MySQL Connector/J can
   only update result sets that have come from queries on tables that
   have at least one primary key, the query must select every primary
   key and the query can only span one table (that is, no joins).
   This is outlined in the JDBC specification.

   Note that this issue only occurs when using updatable result sets,
   and is caused because Connector/J is unable to guarantee that it
   can identify the correct rows within the result set to be updated
   without having a unique reference to each row. There is no
   requirement to have a unique field on a table if you are using
   UPDATE (http://dev.mysql.com/doc/refman/5.0/en/update.html) or
   DELETE (http://dev.mysql.com/doc/refman/5.0/en/delete.html)
   statements on a table where you can individually specify the
   criteria to be matched using a WHERE clause.

   5.3.6: I cannot connect to the MySQL server using Connector/J, and
   I'm sure the connection paramters are correct. 

   Make sure that the skip-networking option has not been enabled on
   your server. Connector/J must be able to communicate with your
   server over TCP/IP, named sockets are not supported. Also ensure
   that you are not filtering connections through a Firewall or other
   network security system. For more information, see Can't connect
   to [local] MySQL server
   (http://dev.mysql.com/doc/refman/5.0/en/common-errors.html#can-not
   -connect-to-server).

   5.3.7: I am trying to connect to my MySQL server within my
   application, but I get the following error and stack trace: 
java.net.SocketException
MESSAGE: Software caused connection abort: recv failed
STACKTRACE:
java.net.SocketException: Software caused connection abort: recv fail
ed
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(Unknown Source)
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1392)
at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:1414)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:625)
at com.mysql.jdbc.Connection.createNewIO(Connection.java:1926)
at com.mysql.jdbc.Connection.<init>(Connection.java:452)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.j
ava:411)

   The error probably indicates that you are using a older version of
   the Connector/J JDBC driver (2.0.14 or 3.0.x) and you are trying
   to connect to a MySQL server with version 4.1x or newer. The older
   drivers are not compatible with 4.1 or newer of MySQL as they do
   not support the newer authentication mechanisms.

   It is likely that the older version of the Connector/J driver
   exists within your application directory or your CLASSPATH
   includes the older Connector/J package.

   5.3.8: My application is deployed through JBoss and I am using
   transactions to handle the statements on the MySQL database. Under
   heavy loads I am getting a error and stack trace, but these only
   occur after a fixed period of heavy activity. 

   This is a JBoss, not Connector/J, issue and is connected to the
   use of transactions. Under heavy loads the time taken for
   transactions to complete can increase, and the error is caused
   because you have exceeded the predefined timeout.

   You can increase the timeout value by setting the
   TransactionTimeout attribute to the TransactionManagerService
   within the /conf/jboss-service.xml file (pre-4.0.3) or
   /deploy/jta-service.xml for JBoss 4.0.3 or later. See
   TransactionTimeoute
   (http://wiki.jboss.org/wiki/Wiki.jsp?page=TransactionTimeout)
   within the JBoss wiki for more information.

   5.3.9: When using gcj an java.io.CharConversionException is raised
   when working with certain character sequences. 

   This is a known issue with gcj which raises an exception when it
   reaches an unknown character or one it cannot convert. You should
   add useJvmCharsetConverters=true to your connection string to
   force character conversion outside of the gcj libraries, or try a
   different JDK.

   5.3.10: Updating a table that contains a primary key that is
   either FLOAT
   (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html) or
   compound primary key that uses FLOAT
   (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html) fails
   to update the table and raises an exception. 

   Connector/J adds conditions to the WHERE clause during an UPDATE
   (http://dev.mysql.com/doc/refman/5.0/en/update.html) to check the
   old values of the primary key. If there is no match then
   Connector/J considers this a failure condition and raises an
   exception.

   The problem is that rounding differences between supplied values
   and the values stored in the database may mean that the values
   never match, and hence the update fails. The issue will affect all
   queries, not just those from Connector/J.

   To prevent this issue, use a primary key that does not use FLOAT
   (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html). If
   you have to use a floating point column in your primary key use
   DOUBLE (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
   or DECIMAL
   (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html) types
   in place of FLOAT
   (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html).

   5.3.11: You get an ER_NET_PACKET_TOO_LARGE
   (http://dev.mysql.com/doc/refman/5.0/en/error_er_net_packet_too_la
   rge.html#error_er_net_packet_too_large) exception, even though the
   binary blob size you want to insert via JDBC is safely below the
   max_allowed_packet
   (http://dev.mysql.com/doc/refman/5.0/en/server-system-variables.ht
   ml#sysvar_max_allowed_packet) size. 

   This is because the hexEscapeBlock() method in
   com.mysql.jdbc.PreparedStatement.streamToBytes() may almost double
   the size of your data.

Chapter 6. Connector/J Support

6.1. Connector/J Community Support

   Sun Microsystems, Inc. provides assistance to the user community
   by means of its mailing lists. For Connector/J related issues, you
   can get help from experienced users by using the MySQL and Java
   mailing list. Archives and subscription information is available
   online at http://lists.mysql.com/java.

   For information about subscribing to MySQL mailing lists or to
   browse list archives, visit http://lists.mysql.com/. See MySQL
   Mailing Lists
   (http://dev.mysql.com/doc/refman/5.1/en/mailing-lists.html).

   Community support from experienced users is also available through
   the JDBC Forum (http://forums.mysql.com/list.php?39). You may also
   find help from other users in the other MySQL Forums, located at
   http://forums.mysql.com. See MySQL Community Support at the MySQL
   Forums (http://dev.mysql.com/doc/refman/5.1/en/forums.html).

6.2. How to Report Connector/J Bugs or Problems

   The normal place to report bugs is http://bugs.mysql.com/, which
   is the address for our bugs database. This database is public, and
   can be browsed and searched by anyone. If you log in to the
   system, you will also be able to enter new reports.

   If you have found a sensitive security bug in MySQL, you can send
   email to security@mysql.com.

   Writing a good bug report takes patience, but doing it right the
   first time saves time both for us and for yourself. A good bug
   report, containing a full test case for the bug, makes it very
   likely that we will fix the bug in the next release.

   This section will help you write your report correctly so that you
   do not waste your time doing things that may not help us much or
   at all.

   If you have a repeatable bug report, please report it to the bugs
   database at http://bugs.mysql.com/. Any bug that we are able to
   repeat has a high chance of being fixed in the next MySQL release.

   To report other problems, you can use one of the MySQL mailing
   lists.

   Remember that it is possible for us to respond to a message
   containing too much information, but not to one containing too
   little. People often omit facts because they think they know the
   cause of a problem and assume that some details do not matter.

   A good principle is this: If you are in doubt about stating
   something, state it. It is faster and less troublesome to write a
   couple more lines in your report than to wait longer for the
   answer if we must ask you to provide information that was missing
   from the initial report.

   The most common errors made in bug reports are (a) not including
   the version number of Connector/J or MySQL used, and (b) not fully
   describing the platform on which Connector/J is installed
   (including the JVM version, and the platform type and version
   number that MySQL itself is installed on).

   This is highly relevant information, and in 99 cases out of 100,
   the bug report is useless without it. Very often we get questions
   like, "Why doesn't this work for me?" Then we find that the
   feature requested wasn't implemented in that MySQL version, or
   that a bug described in a report has already been fixed in newer
   MySQL versions.

   Sometimes the error is platform-dependent; in such cases, it is
   next to impossible for us to fix anything without knowing the
   operating system and the version number of the platform.

   If at all possible, you should create a repeatable, stanalone
   testcase that doesn't involve any third-party classes.

   To streamline this process, we ship a base class for testcases
   with Connector/J, named 'com.mysql.jdbc.util.BaseBugReport'. To
   create a testcase for Connector/J using this class, create your
   own class that inherits from com.mysql.jdbc.util.BaseBugReport and
   override the methods setUp(), tearDown() and runTest().

   In the setUp() method, create code that creates your tables, and
   populates them with any data needed to demonstrate the bug.

   In the runTest() method, create code that demonstrates the bug
   using the tables and data you created in the setUp method.

   In the tearDown() method, drop any tables you created in the
   setUp() method.

   In any of the above three methods, you should use one of the
   variants of the getConnection() method to create a JDBC connection
   to MySQL:

     * getConnection() - Provides a connection to the JDBC URL
       specified in getUrl(). If a connection already exists, that
       connection is returned, otherwise a new connection is created.

     * getNewConnection() - Use this if you need to get a new
       connection for your bug report (that is, there is more than
       one connection involved).

     * getConnection(String url) - Returns a connection using the
       given URL.

     * getConnection(String url, Properties props) - Returns a
       connection using the given URL and properties.

   If you need to use a JDBC URL that is different from
   'jdbc:mysql:///test', override the method getUrl() as well.

   Use the assertTrue(boolean expression) and assertTrue(String
   failureMessage, boolean expression) methods to create conditions
   that must be met in your testcase demonstrating the behavior you
   are expecting (vs. the behavior you are observing, which is why
   you are most likely filing a bug report).

   Finally, create a main() method that creates a new instance of
   your testcase, and calls the run method:
public static void main(String[] args) throws Exception {
      new MyBugReport().run();
 }

   Once you have finished your testcase, and have verified that it
   demonstrates the bug you are reporting, upload it with your bug
   report to http://bugs.mysql.com/.

6.3. Connector/J Change History

   The Connector/J Change History (Changelog) is located with the
   main Changelog for MySQL. See Appendix A, "MySQL Connector/J
   Change History."

Appendix A. MySQL Connector/J Change History

A.1. Changes in MySQL Connector/J 5.1.x

A.1.1. Changes in MySQL Connector/J 5.1.8 (16 July 2009)

   Bugs fixed:

     * The reported milliseconds since the last server packets were
       received/sent was incorrect by a factor of 1000. For example,
       the following method call:
SQLError.createLinkFailureMessageBasedOnHeuristics(
(ConnectionImpl) this.conn,
System.currentTimeMillis() - 1000,
System.currentTimeMillis() - 2000,
e,
false);
       returned the following string:
The last packet successfully received from the server
was 2 milliseconds ago. The last packet sent successfully to the
server was 1 milliseconds ago.
       (Bug#45419: http://bugs.mysql.com/45419)

     * Calling Connection.serverPrepareStatement() variants that do
       not take result set type or concurrency arguments returned
       statements that produced result sets with incorrect defaults,
       namely TYPE_SCROLL_SENSITIVE.
       (Bug#45171: http://bugs.mysql.com/45171)

     * The result set returned by getIndexInfo() did not have the
       format defined in the JDBC API specifications. The fourth
       column, DATA_TYPE, of the result set should be of type
       BOOLEAN. Connector/J however returns CHAR.
       (Bug#44869: http://bugs.mysql.com/44869)

     * The result set returned by getTypeInfo() did not have the
       format defined in the JDBC API specifications. The second
       column, DATA_TYPE, of the result set should be of type
       INTEGER. Connector/J however returns SMALLINT.
       (Bug#44868: http://bugs.mysql.com/44868)

     * The DEFERRABILITY column in database metadata result sets was
       expected to be of type SHORT. However, Connector/J returned it
       as INTEGER.
       This affected the following methods: getImportedKeys(),
       getExportedKeys(), getCrossReference().
       (Bug#44867: http://bugs.mysql.com/44867)

     * The result set returned by getColumns() did not have the
       format defined in the JDBC API specifications. The fifth
       column, DATA_TYPE, of the result set should be of type
       INTEGER. Connector/J however returns SMALLINT.
       (Bug#44865: http://bugs.mysql.com/44865)

     * The result set returned by getVersionColumns() did not have
       the format defined in the JDBC API specifications. The third
       column, DATA_TYPE, of the result set should be of type
       INTEGER. Connector/J however returns SMALLINT.
       (Bug#44863: http://bugs.mysql.com/44863)

     * The result set returned by getBestRowIdentifier() did not have
       the format defined in the JDBC API specifications. The third
       column, DATA_TYPE, of the result set should be of type
       INTEGER. Connector/J however returns SMALLINT.
       (Bug#44862: http://bugs.mysql.com/44862)

     * Connector/J contains logic to generate a message text
       specifically for streaming result sets when there are
       CommunicationsException exceptions generated. However, this
       code was never reached.
       In the CommunicationsException code:
private boolean streamingResultSetInPlay = false;

public CommunicationsException(ConnectionImpl conn, long lastPacketSe
ntTimeMs,
long lastPacketReceivedTimeMs, Exception underlyingException) {

this.exceptionMessage = SQLError.createLinkFailureMessageBasedOnHeuri
stics(conn,
      lastPacketSentTimeMs, lastPacketReceivedTimeMs, underlyingExcep
tion,
      this.streamingResultSetInPlay);
       streamingResultSetInPlay was always false, which in the
       following code in
       SQLError.createLinkFailureMessageBasedOnHeuristics() never
       being executed:
if (streamingResultSetInPlay) {
    exceptionMessageBuf.append(
    Messages.getString("CommunicationsException.ClientWasStreaming"))
; //$NON-NLS-1$
} else {
...
       (Bug#44588: http://bugs.mysql.com/44588)

     * The SQLError.createLinkFailureMessageBasedOnHeuristics()
       method created a message text for communication link failures.
       When certain conditions were met, this message included both
       "last packet sent" and "last packet received" information, but
       when those conditions were not met, only "last packet sent"
       information was provided.
       Information about when the last packet was successfully
       received should be provided in all cases.
       (Bug#44587: http://bugs.mysql.com/44587)

     * Statement.getGeneratedKeys() retained result set instances
       until the statement was closed. This caused memory leaks for
       long-lived statements, or statements used in tight loops.
       (Bug#44056: http://bugs.mysql.com/44056)

     * Using useInformationSchema with
       DatabaseMetaData.getExportedKeys() generated the following
       exception:
com.mysql.jdbc.exceptions.MySQLIntegrityConstraintViolationException:
 Column
'REFERENCED_TABLE_NAME' in where clause is ambiguous
...
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement
.java:1772)
at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.ja
va:1923)
at
com.mysql.jdbc.DatabaseMetaDataUsingInfoSchema.executeMetadataQuery(
DatabaseMetaDataUsingInfoSchema.java:50)
at
com.mysql.jdbc.DatabaseMetaDataUsingInfoSchema.getExportedKeys(
DatabaseMetaDataUsingInfoSchema.java:603)
       (Bug#43714: http://bugs.mysql.com/43714)

     * LoadBalancingConnectionProxy.doPing() did not have blacklist
       awareness.
       LoadBalancingConnectionProxy implemented doPing() to ping all
       underlying connections, but it threw any exceptions it
       encountered during this process.
       With the global blacklist enabled, it catches these
       exceptions, adds the host to the global blacklist, and only
       throws an exception if all hosts are down.
       (Bug#43421: http://bugs.mysql.com/43421)

     * When the MySQL Server was upgraded from 4.0 to 5.0, the
       Connector/J application then failed to connect to the server.
       This was because authentication failed when the application
       ran from EBCDIC platforms such as z/OS.
       (Bug#43071: http://bugs.mysql.com/43071)

     * When connecting with traceProtocol=true, no trace data was
       generated for the server greeting or login request.
       (Bug#43070: http://bugs.mysql.com/43070)

     * Connector/J generated an unhandled
       StringIndexOutOfBoundsException:
java.lang.StringIndexOutOfBoundsException: String index out of range:
 -1
at java.lang.String.substring(String.java:1938)
at com.mysql.jdbc.EscapeProcessor.processTimeToken(EscapeProcessor.ja
va:353)
at com.mysql.jdbc.EscapeProcessor.escapeSQL(EscapeProcessor.java:257)
at com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1546
)
at com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1524
)
       (Bug#42253: http://bugs.mysql.com/42253)

     * A ConcurrentModificationException was generated in
       LoadBalancingConnectionProxy:
java.util.ConcurrentModificationException
 at java.util.HashMap$HashIterator.nextEntry(Unknown Source)
 at java.util.HashMap$KeyIterator.next(Unknown Source)
 at
com.mysql.jdbc.LoadBalancingConnectionProxy.getGlobalBlacklist(LoadBa
lancingConnectionProxy.java:520)
 at com.mysql.jdbc.RandomBalanceStrategy.pickConnection(RandomBalance
Strategy.java:55)
 at
com.mysql.jdbc.LoadBalancingConnectionProxy.pickNewConnection(LoadBal
ancingConnectionProxy.java:414)
 at
com.mysql.jdbc.LoadBalancingConnectionProxy.invoke(LoadBalancingConne
ctionProxy.java:390)
       (Bug#42055: http://bugs.mysql.com/42055)

     * SQL injection was possible when using a string containing
       U+00A5 in a client-side prepared statement, and the character
       set being used was SJIS/Windows-31J.
       (Bug#41730: http://bugs.mysql.com/41730)

     * If there was an apostrophe in a comment in a statement that
       was being sent through Connector/J, the apostrophe was still
       recognized as a quote and put the state machine in
       EscapeTokenizer into the inQuotes state. This led to further
       parse errors.
       For example, consider the following statement:
String sql = "-- Customer's zip code will be fixed\n" +
  "update address set zip_code = 99999\n" +
  "where not regexp '^[0-9]{5}([[.-.]])?([0-9]{4})?$'";
       When passed through Connector/J, the EscapeTokenizer did not
       recognize that the first apostrophe was in a comment and thus
       set inQuotes to true. When that happened, the quote count was
       incorrect and thus the regular expression did not appear to be
       in quotes. With the parser not detecting that the regular
       expression was in quotes, the curly braces were recognized as
       escape sequences and were removed from the regular expression,
       breaking it. The server thus received SQL such as:
-- Customer's zip code will be fixed
update address set zip_code = '99999'
where not regexp '^[0-9]([[.-.]])?([0-9])?$'
       (Bug#41566: http://bugs.mysql.com/41566)

     * MySQL Connector/J 5.1.7 was slower than previous versions when
       the rewriteBatchedStatements option was set to true.

Note
       The performance regression in
       indexOfIgnoreCaseRespectMarker()has been fixed. It has also
       been made possible for the driver to rewrite INSERT statements
       with ON DUPLICATE KEY UPDATE clauses in them, as long as the
       UPDATE clause contains no reference to LAST_INSERT_ID(), as
       that would cause the driver to return bogus values for
       getGeneratedKeys() invocations. This has resulted in improved
       performance over version 5.1.7.
       (Bug#41532: http://bugs.mysql.com/41532)

     * When accessing a result set column by name using
       ResultSetImpl.findColumn() an exception was generated:
java.lang.NullPointerException
at com.mysql.jdbc.ResultSetImpl.findColumn(ResultSetImpl.java:1103)
at com.mysql.jdbc.ResultSetImpl.getShort(ResultSetImpl.java:5415)
at org.apache.commons.dbcp.DelegatingResultSet.getShort(DelegatingRes
ultSet.java:219)
at com.zimbra.cs.db.DbVolume.constructVolume(DbVolume.java:297)
at com.zimbra.cs.db.DbVolume.get(DbVolume.java:197)
at com.zimbra.cs.db.DbVolume.create(DbVolume.java:95)
at com.zimbra.cs.store.Volume.create(Volume.java:227)
at com.zimbra.cs.store.Volume.create(Volume.java:189)
at com.zimbra.cs.service.admin.CreateVolume.handle(CreateVolume.java:
48)
at com.zimbra.soap.SoapEngine.dispatchRequest(SoapEngine.java:428)
at com.zimbra.soap.SoapEngine.dispatch(SoapEngine.java:285)
       (Bug#41484: http://bugs.mysql.com/41484)

     * The RETURN_GENERATED_KEYS flag was being ignored. For example,
       in the following code the RETURN_GENERATED_KEYS flag was
       ignored:
PreparedStatement ps = connection.prepareStatement("INSERT INTO table
  values(?,?)",PreparedStatement.RETURN_GENERATED_KEYS);
       (Bug#41448: http://bugs.mysql.com/41448)

     * When using Connector/J 5.1.7 to connect to MySQL Server 4.1.18
       the following error message was generated:
Thu Dec 11 17:38:21 PST 2008 WARN: Invalid value {1} for server varia
ble named {0},
falling back to sane default of {2}
       This occurred with MySQL Server version that did not support
       auto_increment_increment. The error message should not have
       been generated. (Bug#41416: http://bugs.mysql.com/41416)

     * When DatabaseMetaData.getProcedureColumns() was called, the
       value for LENGTH was always returned as 65535, regardless of
       the column type (fixed or variable) or the actual length of
       the column.
       However, if you obtained the PRECISION value, this was correct
       for both fixed and variable length columns.
       (Bug#41269: http://bugs.mysql.com/41269)

     * PreparedStatement.addBatch() did not check for all parameters
       being set, which led to inconsistent behavior in
       executeBatch(), especially when rewriting batched statements
       into multi-value INSERTs.
       (Bug#41161: http://bugs.mysql.com/41161)

     * Error message strings contained variable values that were not
       expanded. For example:
Mon Nov 17 11:43:18 JST 2008 WARN: Invalid value {1} for server varia
ble named {0},
falling back to sane default of {2}
       (Bug#40772: http://bugs.mysql.com/40772)

     * When using rewriteBatchedStatements=true with:
INSERT INTO table_name_values (...) VALUES (...)
       Query rewriting failed because "values" at the end of the
       table name was mistaken for the reserved keyword. The error
       generated was as follows:
testBug40439(testsuite.simple.TestBug40439)java.sql.BatchUpdateExcept
ion: You have an
error in your SQL syntax; check the manual that corresponds to your M
ySQL server version
for the right syntax to use near 'values (2,'toto',2),(id,data, ordr)
 values
(3,'toto',3),(id,data, ordr) values (' at line 1
at com.mysql.jdbc.PreparedStatement.executeBatchedInserts(PreparedSta
tement.java:1495)
at com.mysql.jdbc.PreparedStatement.executeBatch(PreparedStatement.ja
va:1097)
at testsuite.simple.TestBug40439.testBug40439(TestBug40439.java:42)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorIm
pl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAc
cessorImpl.java:25)
at testsuite.simple.TestBug40439.main(TestBug40439.java:57)
       (Bug#40439: http://bugs.mysql.com/40439)

     * A statement interceptor received the incorrect parameters when
       used with a batched statement.
       (Bug#39426: http://bugs.mysql.com/39426)

     * Using Connector/J 5.1.6 the method ResultSet.getObject
       returned a BYTE[] for following:
SELECT TRIM(rowid) FROM tbl
       Where rowid had a type of INT(11) PRIMARY KEY AUTO_INCREMENT.
       The expected return type was one of CHAR, VARCHAR, CLOB,
       however, a BYTE[] was returned.
       Further, adding functionsNeverReturnBlobs=true to the
       connection string did not have any effect on the return type.
       (Bug#38387: http://bugs.mysql.com/38387)

A.1.2. Changes in MySQL Connector/J 5.1.7 (21 October 2008)

   Functionality added or changed:

     * When statements include ON DUPLICATE UPDATE, and
       rewriteBatchedStatements is set to true, batched statements
       are not rewritten into the form INSERT INTO table VALUES (),
       (), (), instead the statements are executed sequentially.

   Bugs fixed:

     * Statement.getGeneratedKeys() returned two keys when using ON
       DUPLICATE KEY UPDATE and the row was updated, not inserted.
       (Bug#42309: http://bugs.mysql.com/42309)

     * When using the replication driver with autoReconnect=true,
       Connector/J checks in PreparedStatement.execute (also called
       by CallableStatement.execute) to determine if the first
       character of the statement is an "S", in an attempt to block
       all statements that are not read-only-safe, for example
       non-SELECT
       (http://dev.mysql.com/doc/refman/5.0/en/select.html)
       statements. However, this also blocked CALL
       (http://dev.mysql.com/doc/refman/5.0/en/call.html)s to stored
       procedures, even if the stored procedures were defined as SQL
       READ DATA or NO SQL. (Bug#40031: http://bugs.mysql.com/40031)

     * With large result sets ResultSet.findColumn became a
       performance bottleneck.
       (Bug#39962: http://bugs.mysql.com/39962)

     * Connector/J ignored the value of the MySQL Server variable
       auto_increment_increment
       (http://dev.mysql.com/doc/refman/5.0/en/replication-options-ma
       ster.html#sysvar_auto_increment_increment).
       (Bug#39956: http://bugs.mysql.com/39956)

     * Connector/J failed to parse TIMESTAMP
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html) strings
       for nanos correctly. (Bug#39911: http://bugs.mysql.com/39911)

     * When the LoadBalancingConnectionProxy handles a SQLException
       with SQL state starting with "08", it calls
       invalidateCurrentConnection, which in turn removes that
       Connection from liveConnections and the connectionsToHostsMap,
       but it did not add the host to the new global blacklist, if
       the global blacklist was enabled.
       There was also the possibility of a NullPointerException when
       trying to update stats, where
       connectionsToHostsMap.get(this.currentConn) was called:
int hostIndex = ((Integer) this.hostsToListIndexMap.get(this.connecti
onsToHostsMap.get(this.currentConn))).intValue();
       This could happen if a client tried to issue a rollback after
       catching a SQLException caused by a connection failure.
       (Bug#39784: http://bugs.mysql.com/39784)

     * When configuring the Java Replication Driver the last slave
       specified was never used.
       (Bug#39611: http://bugs.mysql.com/39611)

     * When an INSERT ON DUPLICATE KEY UPDATE was performed, and the
       key already existed, the affected-rows value was returned as 1
       instead of 0. (Bug#39352: http://bugs.mysql.com/39352)

     * When using the random load balancing strategy and starting
       with two servers that were both unavailable, an
       IndexOutOfBoundsException was generated when removing a server
       from the whiteList. (Bug#38782: http://bugs.mysql.com/38782)

     * Connector/J threw the following exception when using a
       read-only connection:
        java.sql.SQLException: Connection is read-only. Queries leadi
ng to data
        modification are not allowed.

       (Bug#38747: http://bugs.mysql.com/38747)

     * Connector/J was unable to connect when using a non-latin1
       password. (Bug#37570: http://bugs.mysql.com/37570)

     * The useOldAliasMetadataBehavior connection property was
       ignored. (Bug#35753: http://bugs.mysql.com/35753)

     * Incorrect result is returned from isAfterLast() in streaming
       ResultSet when using setFetchSize(Integer.MIN_VALUE).
       (Bug#35170: http://bugs.mysql.com/35170)

     * When getGeneratedKeys() was called on a statement that had not
       been created with RETURN_GENERATED_KEYS, no exception was
       thrown, and batched executions then returned erroneous values.
       (Bug#34185: http://bugs.mysql.com/34185)

     * The loadBalance bestResponseTime blacklists did not have a
       global state. (Bug#33861: http://bugs.mysql.com/33861)

A.1.3. Changes in MySQL Connector/J 5.1.6 (07 March 2008)

   Functionality added or changed:

     * Multiple result sets were not supported when using streaming
       mode to return data. Both normal statements and the resul sets
       from stored procedures now return multiple results sets, with
       the exception of result sets using registered OUTPUT
       paramaters. (Bug#33678: http://bugs.mysql.com/33678)

     * XAConnections and datasources have been updated to the
       JDBC-4.0 standard.

     * The profiler event handling has been made extensible via the
       profilerEventHandler connection property.

     * Add the verifyServerCertificate propery. If set to "false" the
       driver will not verify the server's certificate when useSSL is
       set to "true"
       When using this feature, the keystore parameters should be
       specified by the clientCertificateKeyStore* properties, rather
       than system properties, as the JSSE doesn't it straightforward
       to have a nonverifying trust store and the "default" key
       store.

   Bugs fixed:

     * DatabaseMetaData.getColumns() returns incorrect COLUMN_SIZE
       value for SET column. (Bug#36830: http://bugs.mysql.com/36830)

     * When trying to read Time values like "00:00:00" with
       ResultSet.getTime(int) an exception is thrown.
       (Bug#36051: http://bugs.mysql.com/36051)

     * JDBC connection URL parameters is ignored when using
       MysqlConnectionPoolDataSource.
       (Bug#35810: http://bugs.mysql.com/35810)

     * When useServerPrepStmts=true and slow query logging is
       enabled, the connector throws a NullPointerException when it
       encounters a slow query.
       (Bug#35666: http://bugs.mysql.com/35666)

     * When using the keyword "loadbalance" in the connection string
       and trying to perform load balancing between two databases,
       the driver appears to hang.
       (Bug#35660: http://bugs.mysql.com/35660)

     * JDBC data type getter method was changed to accept only column
       name, whereas previously it accepted column label.
       (Bug#35610: http://bugs.mysql.com/35610)

     * Prepared statements from pooled connections caused a
       NullPointerException when closed() under JDBC-4.0.
       (Bug#35489: http://bugs.mysql.com/35489)

     * In calling a stored function returning a bigint, an exception
       is encountered beginning:
java.sql.SQLException: java.lang.NumberFormatException: For input str
ing:
       followed by the text of the stored function starting after the
       argument list. (Bug#35199: http://bugs.mysql.com/35199)

     * The JDBC driver uses a different method for evaluating column
       names in resultsetmetadata.getColumnName() and when looking
       for a column in resultset.getObject(columnName). This causes
       Hibernate to fail in queries where the two methods yield
       different results, for example in queries that use alias
       names:
SELECT column AS aliasName from table
       (Bug#35150: http://bugs.mysql.com/35150)

     * MysqlConnectionPoolDataSource does not support
       ReplicationConnection. Notice that we implemented
       com.mysql.jdbc.Connection for ReplicationConnection, however,
       only accessors from ConnectionProperties are implemented (not
       the mutators), and they return values from the currently
       active connection. All other methods from
       com.mysql.jdbc.Connection are implemented, and operate on the
       currently active connection, with the exception of
       resetServerState() and changeUser().
       (Bug#34937: http://bugs.mysql.com/34937)

     * ResultSet.getTimestamp() returns incorrect values for
       month/day of TIMESTAMP
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html)s when
       using server-side prepared statements (not enabled by
       default). (Bug#34913: http://bugs.mysql.com/34913)

     * RowDataStatic does't always set the metadata in ResultSetRow,
       which can lead to failures when unpacking DATE
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html), TIME
       (http://dev.mysql.com/doc/refman/5.0/en/time.html), DATETIME
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html) and
       TIMESTAMP
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html) types
       when using absolute, relative, and previous result set
       navigation methods. (Bug#34762: http://bugs.mysql.com/34762)

     * When calling isValid() on an active connection, if the timeout
       is nonzero then the Connection is invalidated even if the
       Connection is valid. (Bug#34703: http://bugs.mysql.com/34703)

     * It was not possible to truncate a BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) using
       Blog.truncate() when using 0 as an argument.
       (Bug#34677: http://bugs.mysql.com/34677)

     * When using a cursor fetch for a statement, the internal
       prepared statement could cause a memory leak until the
       connection was closed. The internal prepared statement is now
       deleted when the corresponding result set is closed.
       (Bug#34518: http://bugs.mysql.com/34518)

     * When retrieving the column type name of a geometry field, the
       driver would return UNKNOWN instead of GEOMETRY.
       (Bug#34194: http://bugs.mysql.com/34194)

     * Statements with batched values do not return correct values
       for getGeneratedKeys() when rewriteBatchedStatements is set to
       true, and the statement has an ON DUPLICATE KEY UPDATE clause.
       (Bug#34093: http://bugs.mysql.com/34093)

     * The internal class ResultSetInternalMethods referenced the
       nonpublic class com.mysql.jdbc.CachedResultSetMetaData.
       (Bug#33823: http://bugs.mysql.com/33823)

     * A NullPointerException could be raised when using client-side
       prepared statements and enabled the prepared statement cache
       using the cachePrepStmts.
       (Bug#33734: http://bugs.mysql.com/33734)

     * Using server side cursors and cursor fetch, the table metadata
       information would return the data type name instead of the
       column name. (Bug#33594: http://bugs.mysql.com/33594)

     * ResultSet.getTimestamp() would throw a NullPointerException
       instead of a SQLException when called on an empty ResultSet.
       (Bug#33162: http://bugs.mysql.com/33162)

     * Load balancing connection using best response time would
       incorrectly "stick" to hosts that were down when the
       connection was first created.
       We solve this problem with a black list that is used during
       the picking of new hosts. If the black list ends up including
       all configured hosts, the driver will retry for a configurable
       number of times (the retriesAllDown configuration property,
       with a default of 120 times), sleeping 250ms between attempts
       to pick a new connection.
       We've also went ahead and made the balancing strategy
       extensible. To create a new strategy, implement the interface
       com.mysql.jdbc.BalanceStrategy (which also includes our
       standard "extension" interface), and tell the driver to use it
       by passing in the class name via the loadBalanceStrategy
       configuration property.
       (Bug#32877: http://bugs.mysql.com/32877)

     * During a Daylight Savings Time (DST) switchover, there was no
       way to store two timestamp/datetime values , as the hours end
       up being the same when sent as the literal that MySQL
       requires.
       Note that to get this scenario to work with MySQL (since it
       doesn't support per-value timezones), you need to configure
       your server (or session) to be in UTC, and tell the driver not
       to use the legacy date/time code by setting
       useLegacyDatetimeCode to "false". This will cause the driver
       to always convert to/from the server and client timezone
       consistently.
       This bug fix also fixes
       Bug#15604: http://bugs.mysql.com/15604, by adding entirely new
       date/time handling code that can be switched on by
       useLegacyDatetimeCode being set to "false" as a JDBC
       configuration property. For Connector/J 5.1.x, the default is
       "true", in trunk and beyond it will be "false" (that is, the
       old date/time handling code will be deprecated)
       (Bug#32577: http://bugs.mysql.com/32577,
       Bug#15604: http://bugs.mysql.com/15604)

     * When unpacking rows directly, we don't hand off error message
       packets to the internal method which decodes them correctly,
       so no exception is raised, and the driver than hangs trying to
       read rows that aren't there. This tends to happen when calling
       stored procedures, as normal SELECTs won't have an error in
       this spot in the protocol unless an I/O error occurs.
       (Bug#32246: http://bugs.mysql.com/32246)

     * When using a connection from ConnectionPoolDataSource, some
       Connection.prepareStatement() methods would return null
       instead of the prepared statement.
       (Bug#32101: http://bugs.mysql.com/32101)

     * Using CallableStatement.setNull() on a stored function would
       throw an ArrayIndexOutOfBounds exception when setting the last
       parameter to null. (Bug#31823: http://bugs.mysql.com/31823)

     * MysqlValidConnectionChecker doesn't properly handle
       connections created using ReplicationConnection.
       (Bug#31790: http://bugs.mysql.com/31790)

     * Retrieving the server version information for an active
       connection could return invalid information if the default
       character encoding on the host was not ASCII compatible.
       (Bug#31192: http://bugs.mysql.com/31192)

     * Further fixes have been made to this bug in the event that a
       node is nonresponsive. Connector/J will now try a different
       random node instead of waiting for the node to recover before
       continuing. (Bug#31053: http://bugs.mysql.com/31053)

     * ResultSet returned by Statement.getGeneratedKeys() is not
       closed automatically when statement that created it is closed.
       (Bug#30508: http://bugs.mysql.com/30508)

     * DatabaseMetadata.getColumns() doesn't return the correct
       column names if the connection character isn't UTF-8. A bug in
       MySQL server compounded the issue, but was fixed within the
       MySQL 5.0 release cycle. The fix includes changes to all the
       sections of the code that access the server metadata.
       (Bug#20491: http://bugs.mysql.com/20491)

     * Fixed ResultSetMetadata.getColumnName() for result sets
       returned from Statement.getGeneratedKeys() - it was returning
       null instead of "GENERATED_KEY" as in 5.0.x.

A.1.4. Changes in MySQL Connector/J 5.1.5 (09 October 2007)

   The following features are new, compared to the 5.0 series of
   Connector/J

     * Support for JDBC-4.0 NCHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html), NVARCHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html) and NCLOB
       types.

     * JDBC-4.0 support for setting per-connection client information
       (which can be viewed in the comments section of a query via
       SHOW PROCESSLIST
       (http://dev.mysql.com/doc/refman/5.0/en/show-processlist.html)
       on a MySQL server, or can be extended to support custom
       persistence of the information via a public interface).

     * Support for JDBC-4.0 XML processing via JAXP interfaces to
       DOM, SAX and StAX.

     * JDBC-4.0 standardized unwrapping to interfaces that include
       vendor extensions.

   Functionality added or changed:

     * Added autoSlowLog configuration property, overrides
       slowQueryThreshold* properties, driver determines slow queries
       by those that are slower than 5 * stddev of the mean query
       time (outside the 96% percentile).

   Bugs fixed:

     * When a connection is in read-only mode, queries that are
       wrapped in parentheses were incorrectly identified DML
       statements. (Bug#28256: http://bugs.mysql.com/28256)

     * When calling setTimestamp on a prepared statement, the
       timezone information stored in the calendar object was
       ignored. This resulted in the incorrect DATETIME information
       being stored. The following example illustrates this:
Timestamp t = new Timestamp( cal.getTimeInMillis() );
ps.setTimestamp( N, t, cal );
       (Bug#15604: http://bugs.mysql.com/15604)

A.1.5. Changes in MySQL Connector/J 5.1.4 (Not Released)

   Only released internally.

A.1.6. Changes in MySQL Connector/J 5.1.3 (10 September 2007)

   The following features are new, compared to the 5.0 series of
   Connector/J

     * Support for JDBC-4.0 NCHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html), NVARCHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html) and NCLOB
       types.

     * JDBC-4.0 support for setting per-connection client information
       (which can be viewed in the comments section of a query via
       SHOW PROCESSLIST
       (http://dev.mysql.com/doc/refman/5.0/en/show-processlist.html)
       on a MySQL server, or can be extended to support custom
       persistence of the information via a public interface).

     * Support for JDBC-4.0 XML processing via JAXP interfaces to
       DOM, SAX and StAX.

     * JDBC-4.0 standardized unwrapping to interfaces that include
       vendor extensions.

   Functionality added or changed:

     * Connector/J now connects using an initial character set of
       utf-8 solely for the purpose of authentication to allow user
       names or database names in any character set to be used in the
       JDBC connection URL. (Bug#29853: http://bugs.mysql.com/29853)

     * Added two configuration parameters:

          + blobsAreStrings --- Should the driver always treat BLOBs
            as Strings. Added specifically to work around dubious
            metadata returned by the server for GROUP BY clauses.
            Defaults to false.

          + functionsNeverReturnBlobs --- Should the driver always
            treat data from functions returning BLOBs as Strings.
            Added specifically to work around dubious metadata
            returned by the server for GROUP BY clauses. Defaults to
            false.

     * Setting rewriteBatchedStatements to true now causes
       CallableStatements with batched arguments to be re-written in
       the form "CALL (...); CALL (...); ..." to send the batch in as
       few client-server round trips as possible.

     * The driver now picks appropriate internal row representation
       (whole row in one buffer, or individual byte[]s for each
       column value) depending on heuristics, including whether or
       not the row has BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) or TEXT
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) types and
       the overall row-size. The threshold for row size that will
       cause the driver to use a buffer rather than individual
       byte[]s is configured by the configuration property
       largeRowSizeThreshold, which has a default value of 2KB.

     * The data (and how it is stored) for ResultSet rows are now
       behind an interface which allows us (in some cases) to
       allocate less memory per row, in that for "streaming" result
       sets, we re-use the packet used to read rows, since only one
       row at a time is ever active.

     * Added experimental support for statement "interceptors" via
       the com.mysql.jdbc.StatementInterceptor interface, examples
       are in com/mysql/jdbc/interceptors. Implement this interface
       to be placed "in between" query execution, so that it can be
       influenced (currently experimental).

     * The driver will automatically adjust the server session
       variable net_write_timeout
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_net_write_timeout) when it determines its been
       asked for a "streaming" result, and resets it to the previous
       value when the result set has been consumed. (The
       configuration property is named netTimeoutForStreamingResults,
       with a unit of seconds, the value '0' means the driver will
       not try and adjust this value).

     * JDBC-4.0 ease-of-development features including
       auto-registration with the DriverManager via the service
       provider mechanism, standardized Connection validity checks
       and categorized SQLExceptions based on
       recoverability/retry-ability and class of the underlying
       error.

     * Statement.setQueryTimeout()s now affect the entire batch for
       batched statements, rather than the individual statements that
       make up the batch.

     * Errors encountered during
       Statement/PreparedStatement/CallableStatement.executeBatch()
       when rewriteBatchStatements has been set to true now return
       BatchUpdateExceptions according to the setting of
       continueBatchOnError.
       If continueBatchOnError is set to true, the update counts for
       the "chunk" that were sent as one unit will all be set to
       EXECUTE_FAILED, but the driver will attempt to process the
       remainder of the batch. You can determine which "chunk" failed
       by looking at the update counts returned in the
       BatchUpdateException.
       If continueBatchOnError is set to "false", the update counts
       returned will contain all updates up-to and including the
       failed "chunk", with all counts for the failed "chunk" set to
       EXECUTE_FAILED.
       Since MySQL doesn't return multiple error codes for
       multiple-statements, or for multi-value INSERT
       (http://dev.mysql.com/doc/refman/5.0/en/insert.html)/REPLACE
       (http://dev.mysql.com/doc/refman/5.0/en/replace.html), it is
       the application's responsibility to handle determining which
       item(s) in the "chunk" actually failed.

     * New methods on com.mysql.jdbc.Statement:
       setLocalInfileInputStream() and getLocalInfileInputStream():

          + setLocalInfileInputStream() sets an InputStream instance
            that will be used to send data to the MySQL server for a
            LOAD DATA LOCAL INFILE
            (http://dev.mysql.com/doc/refman/5.0/en/load-data.html)
            statement rather than a FileInputStream or URLInputStream
            that represents the path given as an argument to the
            statement.
            This stream will be read to completion upon execution of
            a LOAD DATA LOCAL INFILE
            (http://dev.mysql.com/doc/refman/5.0/en/load-data.html)
            statement, and will automatically be closed by the
            driver, so it needs to be reset before each call to
            execute*() that would cause the MySQL server to request
            data to fulfill the request for LOAD DATA LOCAL INFILE
            (http://dev.mysql.com/doc/refman/5.0/en/load-data.html).
            If this value is set to NULL, the driver will revert to
            using a FileInputStream or URLInputStream as required.

          + getLocalInfileInputStream() returns the InputStream
            instance that will be used to send data in response to a
            LOAD DATA LOCAL INFILE
            (http://dev.mysql.com/doc/refman/5.0/en/load-data.html)
            statement.
            This method returns NULL if no such stream has been set
            via setLocalInfileInputStream().

     * Setting useBlobToStoreUTF8OutsideBMP to true tells the driver
       to treat [MEDIUM/LONG]BLOB columns as [LONG]VARCHAR columns
       holding text encoded in UTF-8 that has characters outside the
       BMP (4-byte encodings), which MySQL server can't handle
       natively.
       Set utf8OutsideBmpExcludedColumnNamePattern to a regex so that
       column names matching the given regex will still be treated as
       BLOBs The regex must follow the patterns used for the
       java.util.regexpackage. The default is to exclude no columns,
       and include all columns.
       Set utf8OutsideBmpIncludedColumnNamePattern to specify
       exclusion rules to utf8OutsideBmpExcludedColumnNamePattern".
       The regex must follow the patterns used for the
       java.util.regex package.

   Bugs fixed:

     * setObject(int, Object, int, int) delegate in
       PreparedStatmentWrapper delegates to wrong method.
       (Bug#30892: http://bugs.mysql.com/30892)

     * NPE with null column values when padCharsWithSpace is set to
       true. (Bug#30851: http://bugs.mysql.com/30851)

     * Collation on VARBINARY
       (http://dev.mysql.com/doc/refman/5.0/en/binary-varbinary.html)
       column types would be misidentified. A fix has been added, but
       this fix only works for MySQL server versions 5.0.25 and
       newer, since earlier versions didn't consistently return
       correct metadata for functions, and thus results from
       subqueries and functions were indistinguishable from each
       other, leading to type-related bugs.
       (Bug#30664: http://bugs.mysql.com/30664)

     * An ArithmeticException or NullPointerException would be raised
       when the batch had zero members and
       rewriteBatchedStatements=true when addBatch() was never
       called, or executeBatch() was called immediately after
       clearBatch(). (Bug#30550: http://bugs.mysql.com/30550)

     * Closing a load-balanced connection would cause a
       ClassCastException. (Bug#29852: http://bugs.mysql.com/29852)

     * Connection checker for JBoss didn't use same method parameters
       via reflection, causing connections to always seem "bad".
       (Bug#29106: http://bugs.mysql.com/29106)

     * DatabaseMetaData.getTypeInfo() for the types DECIMAL
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       and NUMERIC
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       will return a precision of 254 for server versions older than
       5.0.3, 64 for versions 5.0.3-5.0.5 and 65 for versions newer
       than 5.0.5. (Bug#28972: http://bugs.mysql.com/28972)

     * CallableStatement.executeBatch() doesn't work when connection
       property noAccessToProcedureBodies has been set to true.
       The fix involves changing the behavior of
       noAccessToProcedureBodies,in that the driver will now report
       all paramters as "IN" paramters but allow callers to call
       registerOutParameter() on them without throwing an exception.
       (Bug#28689: http://bugs.mysql.com/28689)

     * DatabaseMetaData.getColumns() doesn't contain SCOPE_* or
       IS_AUTOINCREMENT columns.
       (Bug#27915: http://bugs.mysql.com/27915)

     * Schema objects with identifiers other than the connection
       character aren't retrieved correctly in ResultSetMetadata.
       (Bug#27867: http://bugs.mysql.com/27867)

     * Connection.getServerCharacterEncoding() doesn't work for
       servers with version >= 4.1.
       (Bug#27182: http://bugs.mysql.com/27182)

     * The automated SVN revisions in DBMD.getDriverVersion(). The
       SVN revision of the directory is now inserted into the version
       information during the build.
       (Bug#21116: http://bugs.mysql.com/21116)

     * Specifying a "validation query" in your connection pool that
       starts with "/* ping */" _exactly_ will cause the driver to
       instead send a ping to the server and return a fake result set
       (much lighter weight), and when using a ReplicationConnection
       or a LoadBalancedConnection, will send the ping across all
       active connections.

A.1.7. Changes in MySQL Connector/J 5.1.2 (29 June 2007)

   This is a new Beta development release, fixing recently discovered
   bugs.

   Functionality added or changed:

     * Setting the configuration property rewriteBatchedStatements to
       true will now cause the driver to rewrite batched prepared
       statements with more than 3 parameter sets in a batch into
       multi-statements (separated by ";") if they are not plain
       (that is, without SELECT
       (http://dev.mysql.com/doc/refman/5.0/en/select.html) or ON
       DUPLICATE KEY UPDATE clauses) INSERT
       (http://dev.mysql.com/doc/refman/5.0/en/insert.html) or
       REPLACE (http://dev.mysql.com/doc/refman/5.0/en/replace.html)
       statements.

A.1.8. Changes in MySQL Connector/J 5.1.1 (22 June 2007)

   This is a new Alpha development release, adding new features and
   fixing recently discovered bugs.

   Functionality added or changed:

     * Incompatible Change: Pulled vendor-extension methods of
       Connection implementation out into an interface to support
       java.sql.Wrapper functionality from ConnectionPoolDataSource.
       The vendor extensions are javadoc'd in the
       com.mysql.jdbc.Connection interface.
       For those looking further into the driver implementation, it
       is not an API that is used for plugability of implementations
       inside our driver (which is why there are still references to
       ConnectionImpl throughout the code).
       We've also added server and client prepareStatement() methods
       that cover all of the variants in the JDBC API.
       Connection.serverPrepare(String) has been re-named to
       Connection.serverPrepareStatement() for consistency with
       Connection.clientPrepareStatement().

     * Row navigation now causes any streams/readers open on the
       result set to be closed, as in some cases we're reading
       directly from a shared network packet and it will be
       overwritten by the "next" row.

     * Made it possible to retrieve prepared statement parameter
       bindings (to be used in StatementInterceptors, primarily).

     * Externalized the descriptions of connection properties.

     * The data (and how it is stored) for ResultSet rows are now
       behind an interface which allows us (in some cases) to
       allocate less memory per row, in that for "streaming" result
       sets, we re-use the packet used to read rows, since only one
       row at a time is ever active.

     * Similar to Connection, we pulled out vendor extensions to
       Statement into an interface named com.mysql.Statement, and
       moved the Statement class into com.mysql.StatementImpl. The
       two methods (javadoc'd in com.mysql.Statement are
       enableStreamingResults(), which already existed, and
       disableStreamingResults() which sets the statement instance
       back to the fetch size and result set type it had before
       enableStreamingResults() was called.

     * Driver now picks appropriate internal row representation
       (whole row in one buffer, or individual byte[]s for each
       column value) depending on heuristics, including whether or
       not the row has BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) or TEXT
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) types and
       the overall row-size. The threshold for row size that will
       cause the driver to use a buffer rather than individual
       byte[]s is configured by the configuration property
       largeRowSizeThreshold, which has a default value of 2KB.

     * Added experimental support for statement "interceptors" via
       the com.mysql.jdbc.StatementInterceptor interface, examples
       are in com/mysql/jdbc/interceptors.
       Implement this interface to be placed "in between" query
       execution, so that you can influence it. (currently
       experimental).
       StatementInterceptors are "chainable" when configured by the
       user, the results returned by the "current" interceptor will
       be passed on to the next on in the chain, from left-to-right
       order, as specified by the user in the JDBC configuration
       property statementInterceptors.

     * See the sources (fully javadoc'd) for
       com.mysql.jdbc.StatementInterceptor for more details until we
       iron out the API and get it documented in the manual.

     * Setting rewriteBatchedStatements to true now causes
       CallableStatements with batched arguments to be re-written in
       the form CALL (...); CALL (...); ... to send the batch in as
       few client-server round trips as possible.

A.1.9. Changes in MySQL Connector/J 5.1.0 (11 April 2007)

   This is the first public alpha release of the current Connector/J
   5.1 development branch, providing an insight to upcoming features.
   Although some of these are still under development, this release
   includes the following new features and changes (in comparison to
   the current Connector/J 5.0 production release):

   Important change: Due to a number of issues with the use of
   server-side prepared statements, Connector/J 5.0.5 has disabled
   their use by default. The disabling of server-side prepared
   statements does not affect the operation of the connector in any
   way.

   To enable server-side prepared statements you must add the
   following configuration property to your connector string:
useServerPrepStmts=true

   The default value of this property is false (that is, Connector/J
   does not use server-side prepared statements).

Note

   The disabling of server-side prepared statements does not affect
   the operation of the connector. However, if you use the
   useTimezone=true connection option and use client-side prepared
   statements (instead of server-side prepared statements) you should
   also set useSSPSCompatibleTimezoneShift=true.

   Functionality added or changed:

     * Refactored CommunicationsException into a JDBC-3.0 version,
       and a JDBC-4.0 version (which extends SQLRecoverableException,
       now that it exists).

Note
       This change means that if you were catching
       com.mysql.jdbc.CommunicationsException in your applications
       instead of looking at the SQLState class of 08, and are moving
       to Java 6 (or newer), you need to change your imports to that
       exception to be
       com.mysql.jdbc.exceptions.jdbc4.CommunicationsException, as
       the old class will not be instantiated for communications
       link-related errors under Java 6.

     * Added support for JDBC-4.0 categorized SQLExceptions.

     * Added support for JDBC-4.0's NCLOB, and NCHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html)/NVARCHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html) types.

     * com.mysql.jdbc.java6.javac --- full path to your Java-6 javac
       executable

     * Added support for JDBC-4.0's SQLXML interfaces.

     * Re-worked Ant buildfile to build JDBC-4.0 classes separately,
       as well as support building under Eclipse (since Eclipse can't
       mix/match JDKs).
       To build, you must set JAVA_HOME to J2SDK-1.4.2 or Java-5, and
       set the following properties on your Ant command line:

          + com.mysql.jdbc.java6.javac --- full path to your Java-6
            javac executable

          + com.mysql.jdbc.java6.rtjar --- full path to your Java-6
            rt.jar file

     * New feature --- driver will automatically adjust session
       variable net_write_timeout
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_net_write_timeout) when it determines it has
       been asked for a "streaming" result, and resets it to the
       previous value when the result set has been consumed.
       (configuration property is named netTimeoutForStreamingResults
       value and has a unit of seconds, the value 0 means the driver
       will not try and adjust this value).

     * Added support for JDBC-4.0's client information. The backend
       storage of information provided via Connection.setClientInfo()
       and retrieved by Connection.getClientInfo() is pluggable by
       any class that implements the
       com.mysql.jdbc.JDBC4ClientInfoProvider interface and has a
       no-args constructor.
       The implementation used by the driver is configured using the
       clientInfoProvider configuration property (with a default of
       value of com.mysql.jdbc.JDBC4CommentClientInfoProvider, an
       implementation which lists the client information as a comment
       prepended to every query sent to the server).
       This functionality is only available when using Java-6 or
       newer.

     * com.mysql.jdbc.java6.rtjar --- full path to your Java-6 rt.jar
       file

     * Added support for JDBC-4.0's Wrapper interface.

A.2. Changes in MySQL Connector/J 5.0.x

A.2.1. Changes in MySQL Connector/J 5.0.8 (09 October 2007)

   Functionality added or changed:

     * blobsAreStrings --- Should the driver always treat BLOBs as
       Strings. Added specifically to work around dubious metadata
       returned by the server for GROUP BY clauses. Defaults to
       false.

     * Added two configuration parameters:

          + blobsAreStrings --- Should the driver always treat BLOBs
            as Strings. Added specifically to work around dubious
            metadata returned by the server for GROUP BY clauses.
            Defaults to false.

          + functionsNeverReturnBlobs --- Should the driver always
            treat data from functions returning BLOBs as Strings.
            Added specifically to work around dubious metadata
            returned by the server for GROUP BY clauses. Defaults to
            false.

     * functionsNeverReturnBlobs --- Should the driver always treat
       data from functions returning BLOBs as Strings. Added
       specifically to work around dubious metadata returned by the
       server for GROUP BY clauses. Defaults to false.

     * XAConnections now start in auto-commit mode (as per JDBC-4.0
       specification clarification).

     * Driver will now fall back to sane defaults for
       max_allowed_packet
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_max_allowed_packet) and net_buffer_length
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_net_buffer_length) if the server reports them
       incorrectly (and will log this situation at WARN level, since
       it is actually an error condition).

   Bugs fixed:

     * Connections established using URLs of the form
       jdbc:mysql:loadbalance:// weren't doing failover if they tried
       to connect to a MySQL server that was down. The driver now
       attempts connections to the next "best" (depending on the load
       balance strategy in use) server, and continues to attempt
       connecting to the next "best" server every 250 milliseconds
       until one is found that is up and running or 5 minutes has
       passed.
       If the driver gives up, it will throw the last-received
       SQLException. (Bug#31053: http://bugs.mysql.com/31053)

     * setObject(int, Object, int, int) delegate in
       PreparedStatmentWrapper delegates to wrong method.
       (Bug#30892: http://bugs.mysql.com/30892)

     * NPE with null column values when padCharsWithSpace is set to
       true. (Bug#30851: http://bugs.mysql.com/30851)

     * Collation on VARBINARY
       (http://dev.mysql.com/doc/refman/5.0/en/binary-varbinary.html)
       column types would be misidentified. A fix has been added, but
       this fix only works for MySQL server versions 5.0.25 and
       newer, since earlier versions didn't consistently return
       correct metadata for functions, and thus results from
       subqueries and functions were indistinguishable from each
       other, leading to type-related bugs.
       (Bug#30664: http://bugs.mysql.com/30664)

     * An ArithmeticException or NullPointerException would be raised
       when the batch had zero members and
       rewriteBatchedStatements=true when addBatch() was never
       called, or executeBatch() was called immediately after
       clearBatch(). (Bug#30550: http://bugs.mysql.com/30550)

     * Closing a load-balanced connection would cause a
       ClassCastException. (Bug#29852: http://bugs.mysql.com/29852)

     * Connection checker for JBoss didn't use same method parameters
       via reflection, causing connections to always seem "bad".
       (Bug#29106: http://bugs.mysql.com/29106)

     * DatabaseMetaData.getTypeInfo() for the types DECIMAL
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       and NUMERIC
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       will return a precision of 254 for server versions older than
       5.0.3, 64 for versions 5.0.3-5.0.5 and 65 for versions newer
       than 5.0.5. (Bug#28972: http://bugs.mysql.com/28972)

     * CallableStatement.executeBatch() doesn't work when connection
       property noAccessToProcedureBodies has been set to true.
       The fix involves changing the behavior of
       noAccessToProcedureBodies,in that the driver will now report
       all paramters as "IN" paramters but allow callers to call
       registerOutParameter() on them without throwing an exception.
       (Bug#28689: http://bugs.mysql.com/28689)

     * When a connection is in read-only mode, queries that are
       wrapped in parentheses were incorrectly identified DML
       statements. (Bug#28256: http://bugs.mysql.com/28256)

     * UNSIGNED types not reported via DBMD.getTypeInfo(), and
       capitalization of type names is not consistent between
       DBMD.getColumns(), RSMD.getColumnTypeName() and
       DBMD.getTypeInfo().
       This fix also ensures that the precision of UNSIGNED MEDIUMINT
       and UNSIGNED BIGINT is reported correctly via
       DBMD.getColumns(). (Bug#27916: http://bugs.mysql.com/27916)

     * DatabaseMetaData.getColumns() doesn't contain SCOPE_* or
       IS_AUTOINCREMENT columns.
       (Bug#27915: http://bugs.mysql.com/27915)

     * Schema objects with identifiers other than the connection
       character aren't retrieved correctly in ResultSetMetadata.
       (Bug#27867: http://bugs.mysql.com/27867)

     * Cached metadata with PreparedStatement.execute() throws
       NullPointerException. (Bug#27412: http://bugs.mysql.com/27412)

     * Connection.getServerCharacterEncoding() doesn't work for
       servers with version >= 4.1.
       (Bug#27182: http://bugs.mysql.com/27182)

     * The automated SVN revisions in DBMD.getDriverVersion(). The
       SVN revision of the directory is now inserted into the version
       information during the build.
       (Bug#21116: http://bugs.mysql.com/21116)

     * Specifying a "validation query" in your connection pool that
       starts with "/* ping */" _exactly_ will cause the driver to
       instead send a ping to the server and return a fake result set
       (much lighter weight), and when using a ReplicationConnection
       or a LoadBalancedConnection, will send the ping across all
       active connections.

A.2.2. Changes in MySQL Connector/J 5.0.7 (20 July 2007)

   Functionality added or changed:

     * The driver will now automatically set useServerPrepStmts to
       true when useCursorFetch has been set to true, since the
       feature requires server-side prepared statements in order to
       function.

     * tcpKeepAlive - Should the driver set SO_KEEPALIVE (default
       true)?

     * Give more information in EOFExceptions thrown out of MysqlIO
       (how many bytes the driver expected to read, how many it
       actually read, say that communications with the server were
       unexpectedly lost).

     * Driver detects when it is running in a ColdFusion MX server
       (tested with version 7), and uses the configuration bundle
       coldFusion, which sets useDynamicCharsetInfo to false (see
       previous entry), and sets useLocalSessionState and
       autoReconnect to true.

     * tcpNoDelay - Should the driver set SO_TCP_NODELAY (disabling
       the Nagle Algorithm, default true)?

     * Added configuration property slowQueryThresholdNanos - if
       useNanosForElapsedTime is set to true, and this property is
       set to a nonzero value the driver will use this threshold (in
       nanosecond units) to determine if a query was slow, instead of
       using millisecond units.

     * tcpRcvBuf - Should the driver set SO_RCV_BUF to the given
       value? The default value of '0', means use the platform
       default value for this property.

     * Setting useDynamicCharsetInfo to false now causes driver to
       use static lookups for collations as well (makes
       ResultSetMetadata.isCaseSensitive() much more efficient, which
       leads to performance increase for ColdFusion, which calls this
       method for every column on every table it sees, it appears).

     * Added configuration properties to allow tuning of TCP/IP
       socket parameters:

          + tcpNoDelay - Should the driver set SO_TCP_NODELAY
            (disabling the Nagle Algorithm, default true)?

          + tcpKeepAlive - Should the driver set SO_KEEPALIVE
            (default true)?

          + tcpRcvBuf - Should the driver set SO_RCV_BUF to the given
            value? The default value of '0', means use the platform
            default value for this property.

          + tcpSndBuf - Should the driver set SO_SND_BUF to the given
            value? The default value of '0', means use the platform
            default value for this property.

          + tcpTrafficClass - Should the driver set traffic class or
            type-of-service fields? See the documentation for
            java.net.Socket.setTrafficClass() for more information.

     * Setting the configuration parameter useCursorFetch to true for
       MySQL-5.0+ enables the use of cursors that allow Connector/J
       to save memory by fetching result set rows in chunks (where
       the chunk size is set by calling setFetchSize() on a Statement
       or ResultSet) by using fully-materialized cursors on the
       server.

     * tcpSndBuf - Should the driver set SO_SND_BUF to the given
       value? The default value of '0', means use the platform
       default value for this property.

     * tcpTrafficClass - Should the driver set traffic class or
       type-of-service fields? See the documentation for
       java.net.Socket.setTrafficClass() for more information.

     * Added new debugging functionality - Setting configuration
       property includeInnodbStatusInDeadlockExceptions to true will
       cause the driver to append the output of SHOW ENGINE INNODB
       STATUS
       (http://dev.mysql.com/doc/refman/5.0/en/show-engine.html) to
       deadlock-related exceptions, which will enumerate the current
       locks held inside InnoDB.

     * Added configuration property useNanosForElapsedTime - for
       profiling/debugging functionality that measures elapsed time,
       should the driver try to use nanoseconds resolution if
       available (requires JDK >= 1.5)?

Note
       If useNanosForElapsedTime is set to true, and this property is
       set to "0" (or left default), then elapsed times will still be
       measured in nanoseconds (if possible), but the slow query
       threshold will be converted from milliseconds to nanoseconds,
       and thus have an upper bound of approximately 2000
       milliseconds (as that threshold is represented as an integer,
       not a long).

   Bugs fixed:

     * Don't send any file data in response to LOAD DATA LOCAL INFILE
       if the feature is disabled at the client side. This is to
       prevent a malicious server or man-in-the-middle from asking
       the client for data that the client is not expecting. Thanks
       to Jan Kneschke for discovering the exploit and Andrey
       "Poohie" Hristov, Konstantin Osipov and Sergei Golubchik for
       discussions about implications and possible fixes.
       (Bug#29605: http://bugs.mysql.com/29605)

     * Parser in client-side prepared statements runs to end of
       statement, rather than end-of-line for '#' comments. Also
       added support for '--' single-line comments.
       (Bug#28956: http://bugs.mysql.com/28956)

     * Parser in client-side prepared statements eats character
       following '/' if it is not a multi-line comment.
       (Bug#28851: http://bugs.mysql.com/28851)

     * PreparedStatement.getMetaData() for statements containing
       leading one-line comments is not returned correctly.
       As part of this fix, we also overhauled detection of DML for
       executeQuery() and SELECT
       (http://dev.mysql.com/doc/refman/5.0/en/select.html)s for
       executeUpdate() in plain and prepared statements to be aware
       of the same types of comments.
       (Bug#28469: http://bugs.mysql.com/28469)

A.2.3. Changes in MySQL Connector/J 5.0.6 (15 May 2007)

   Functionality added or changed:

     * Added an experimental load-balanced connection designed for
       use with SQL nodes in a MySQL Cluster/NDB environment (This is
       not for master-slave replication. For that, we suggest you
       look at ReplicationConnection or lbpool).
       If the JDBC URL starts with
       jdbc:mysql:loadbalance://host-1,host-2,...host-n, the driver
       will create an implementation of java.sql.Connection that load
       balances requests across a series of MySQL JDBC connections to
       the given hosts, where the balancing takes place after
       transaction commit.
       Therefore, for this to work (at all), you must use
       transactions, even if only reading data.
       Physical connections to the given hosts will not be created
       until needed.
       The driver will invalidate connections that it detects have
       had communication errors when processing a request. A new
       connection to the problematic host will be attempted the next
       time it is selected by the load balancing algorithm.
       There are two choices for load balancing algorithms, which may
       be specified by the loadBalanceStrategy JDBC URL configuration
       property:

          + random --- the driver will pick a random host for each
            request. This tends to work better than round-robin, as
            the randomness will somewhat account for spreading loads
            where requests vary in response time, while round-robin
            can sometimes lead to overloaded nodes if there are
            variations in response times across the workload.

          + bestResponseTime --- the driver will route the request to
            the host that had the best response time for the previous
            transaction.

     * bestResponseTime --- the driver will route the request to the
       host that had the best response time for the previous
       transaction.

     * Added configuration property padCharsWithSpace (defaults to
       false). If set to true, and a result set column has the CHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html) type and
       the value does not fill the amount of characters specified in
       the DDL for the column, the driver will pad the remaining
       characters with space (for ANSI compliance).

     * When useLocalSessionState is set to true and connected to a
       MySQL-5.0 or later server, the JDBC driver will now determine
       whether an actual commit or rollback statement needs to be
       sent to the database when Connection.commit() or
       Connection.rollback() is called.
       This is especially helpful for high-load situations with
       connection pools that always call Connection.rollback() on
       connection check-in/check-out because it avoids a round-trip
       to the server.

     * Added configuration property useDynamicCharsetInfo. If set to
       false (the default), the driver will use a per-connection
       cache of character set information queried from the server
       when necessary, or when set to true, use a built-in static
       mapping that is more efficient, but isn't aware of custom
       character sets or character sets implemented after the release
       of the JDBC driver.

Note
       This only affects the padCharsWithSpace configuration property
       and the ResultSetMetaData.getColumnDisplayWidth() method.

     * New configuration property, enableQueryTimeouts (default
       true).
       When enabled, query timeouts set via
       Statement.setQueryTimeout() use a shared java.util.Timer
       instance for scheduling. Even if the timeout doesn't expire
       before the query is processed, there will be memory used by
       the TimerTask for the given timeout which won't be reclaimed
       until the time the timeout would have expired if it hadn't
       been cancelled by the driver. High-load environments might
       want to consider disabling this functionality. (this
       configuration property is part of the maxPerformance
       configuration bundle).

     * Give better error message when "streaming" result sets, and
       the connection gets clobbered because of exceeding
       net_write_timeout
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_net_write_timeout) on the server.

     * random --- the driver will pick a random host for each
       request. This tends to work better than round-robin, as the
       randomness will somewhat account for spreading loads where
       requests vary in response time, while round-robin can
       sometimes lead to overloaded nodes if there are variations in
       response times across the workload.

     * com.mysql.jdbc.[NonRegistering]Driver now understands URLs of
       the format jdbc:mysql:replication:// and
       jdbc:mysql:loadbalance:// which will create a
       ReplicationConnection (exactly like when using
       [NonRegistering]ReplicationDriver) and an experimental
       load-balanced connection designed for use with SQL nodes in a
       MySQL Cluster/NDB environment, respectively.
       In an effort to simplify things, we're working on deprecating
       multiple drivers, and instead specifying different core
       behavior based upon JDBC URL prefixes, so watch for
       [NonRegistering]ReplicationDriver to eventually disappear, to
       be replaced with com.mysql.jdbc[NonRegistering]Driver with the
       new URL prefix.

     * Fixed issue where a failed-over connection would let an
       application call setReadOnly(false), when that call should be
       ignored until the connection is reconnected to a writable
       master unless failoverReadOnly had been set to false.

     * Driver will now use INSERT INTO ... VALUES (DEFAULT)form of
       statement for updatable result sets for ResultSet.insertRow(),
       rather than pre-populating the insert row with values from
       DatabaseMetaData.getColumns()(which results in a SHOW FULL
       COLUMNS
       (http://dev.mysql.com/doc/refman/5.0/en/show-columns.html) on
       the server for every result set). If an application requires
       access to the default values before insertRow() has been
       called, the JDBC URL should be configured with
       populateInsertRowWithDefaultValues set to true.
       This fix specifically targets performance issues with
       ColdFusion and the fact that it seems to ask for updatable
       result sets no matter what the application does with them.

     * More intelligent initial packet sizes for the "shared" packets
       are used (512 bytes, rather than 16K), and initial packets
       used during handshake are now sized appropriately as to not
       require reallocation.

   Bugs fixed:

     * More useful error messages are generated when the driver
       thinks a result set is not updatable. (Thanks to Ashley
       Martens for the patch).
       (Bug#28085: http://bugs.mysql.com/28085)

     * Connection.getTransactionIsolation() uses "SHOW VARIABLES
       LIKE" which is very inefficient on MySQL-5.0+ servers.
       (Bug#27655: http://bugs.mysql.com/27655)

     * Fixed issue where calling getGeneratedKeys() on a prepared
       statement after calling execute() didn't always return the
       generated keys (executeUpdate() worked fine however).
       (Bug#27655: http://bugs.mysql.com/27655)

     * CALL /* ... */ some_proc() doesn't work. As a side effect of
       this fix, you can now use /* */ and # comments when preparing
       statements using client-side prepared statement emulation.
       If the comments happen to contain parameter markers (?), they
       will be treated as belonging to the comment (that is, not
       recognized) rather than being a parameter of the statement.

Note
       The statement when sent to the server will contain the
       comments as-is, they're not stripped during the process of
       preparing the PreparedStatement or CallableStatement.
       (Bug#27400: http://bugs.mysql.com/27400)

     * ResultSet.get*() with a column index < 1 returns misleading
       error message. (Bug#27317: http://bugs.mysql.com/27317)

     * Using ResultSet.get*() with a column index less than 1 returns
       a misleading error message.
       (Bug#27317: http://bugs.mysql.com/27317)

     * Comments in DDL of stored procedures/functions confuse
       procedure parser, and thus metadata about them can not be
       created, leading to inability to retrieve said metadata, or
       execute procedures that have certain comments in them.
       (Bug#26959: http://bugs.mysql.com/26959)

     * Fast date/time parsing doesn't take into account 00:00:00 as a
       legal value. (Bug#26789: http://bugs.mysql.com/26789)

     * PreparedStatement is not closed in BlobFromLocator.getBytes().
       (Bug#26592: http://bugs.mysql.com/26592)

     * When the configuration property useCursorFetch was set to
       true, sometimes server would return new, more exact metadata
       during the execution of the server-side prepared statement
       that enables this functionality, which the driver ignored
       (using the original metadata returned during prepare()),
       causing corrupt reading of data due to type mismatch when the
       actual rows were returned.
       (Bug#26173: http://bugs.mysql.com/26173)

     * CallableStatements with OUT/INOUT parameters that are "binary"
       (BLOB (http://dev.mysql.com/doc/refman/5.0/en/blob.html), BIT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html),
       (VAR)BINARY, JAVA_OBJECT) have extra 7 bytes.
       (Bug#25715: http://bugs.mysql.com/25715)

     * Whitespace surrounding storage/size specifiers in stored
       procedure parameters declaration causes NumberFormatException
       to be thrown when calling stored procedure on JDK-1.5 or
       newer, as the Number classes in JDK-1.5+ are whitespace
       intolerant. (Bug#25624: http://bugs.mysql.com/25624)

     * Client options not sent correctly when using SSL, leading to
       stored procedures not being able to return results. Thanks to
       Don Cohen for the bug report, testcase and patch.
       (Bug#25545: http://bugs.mysql.com/25545)

     * Statement.setMaxRows() is not effective on result sets
       materialized from cursors.
       (Bug#25517: http://bugs.mysql.com/25517)

     * BIT(> 1) is returned as java.lang.String from
       ResultSet.getObject() rather than byte[].
       (Bug#25328: http://bugs.mysql.com/25328)

A.2.4. Changes in MySQL Connector/J 5.0.5 (02 March 2007)

   Functionality added or changed:

     * Usage Advisor will now issue warnings for result sets with
       large numbers of rows. You can configure the trigger value by
       using the resultSetSizeThreshold parameter, which has a
       default value of 100.

     * The rewriteBatchedStatements feature can now be used with
       server-side prepared statements.

     * Important change: Due to a number of issues with the use of
       server-side prepared statements, Connector/J 5.0.5 has
       disabled their use by default. The disabling of server-side
       prepared statements does not affect the operation of the
       connector in any way.
       To enable server-side prepared statements you must add the
       following configuration property to your connector string:
useServerPrepStmts=true
       The default value of this property is false (that is,
       Connector/J does not use server-side prepared statements).

     * Improved speed of datetime parsing for ResultSets that come
       from plain or nonserver-side prepared statements. You can
       enable old implementation with useFastDateParsing=false as a
       configuration parameter.

     * Usage Advisor now detects empty results sets and does not
       report on columns not referenced in those empty sets.

     * Fixed logging of XA commands sent to server, it is now
       configurable via logXaCommands property (defaults to false).

     * Added configuration property localSocketAddress, which is the
       host name or IP address given to explicitly configure the
       interface that the driver will bind the client side of the
       TCP/IP connection to when connecting.

     * We've added a new configuration option
       treatUtilDateAsTimestamp, which is false by default, as (1) We
       already had specific behavior to treat java.util.Date as a
       java.sql.Timestamp because it is useful to many folks, and (2)
       that behavior will very likely be required for drivers
       JDBC-post-4.0.

   Bugs fixed:

     * Connection property socketFactory wasn't exposed via correctly
       named mutator/accessor, causing data source implementations
       that use JavaBean naming conventions to set properties to fail
       to set the property (and in the case of SJAS, fail silently
       when trying to set this parameter).
       (Bug#26326: http://bugs.mysql.com/26326)

     * A query execution which timed out did not always throw a
       MySQLTimeoutException.
       (Bug#25836: http://bugs.mysql.com/25836)

     * Storing a java.util.Date object in a BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) column
       would not be serialized correctly during setObject.
       (Bug#25787: http://bugs.mysql.com/25787)

     * Timer instance used for Statement.setQueryTimeout() created
       per-connection, rather than per-VM, causing memory leak.
       (Bug#25514: http://bugs.mysql.com/25514)

     * EscapeProcessor gets confused by multiple backslashes. We now
       push the responsibility of syntax errors back on to the server
       for most escape sequences.
       (Bug#25399: http://bugs.mysql.com/25399)

     * INOUT parameters in CallableStatements get doubly-escaped.
       (Bug#25379: http://bugs.mysql.com/25379)

     * When using the rewriteBatchedStatements connection option with
       PreparedState.executeBatch() an internal memory leak would
       occur. (Bug#25073: http://bugs.mysql.com/25073)

     * Fixed issue where field-level for metadata from
       DatabaseMetaData when using INFORMATION_SCHEMA didn't have
       references to current connections, sometimes leading to Null
       Pointer Exceptions (NPEs) when introspecting them via
       ResultSetMetaData. (Bug#25073: http://bugs.mysql.com/25073)

     * StringUtils.indexOfIgnoreCaseRespectQuotes() isn't
       case-insensitive on the first character of the target. This
       bug also affected rewriteBatchedStatements functionality when
       prepared statements did not use uppercase for the VALUES
       clause. (Bug#25047: http://bugs.mysql.com/25047)

     * Client-side prepared statement parser gets confused by in-line
       comments /*...*/ and therefore cannot rewrite batch statements
       or reliably detect the type of statements when they are used.
       (Bug#25025: http://bugs.mysql.com/25025)

     * Results sets from UPDATE
       (http://dev.mysql.com/doc/refman/5.0/en/update.html)
       statements that are part of multi-statement queries would
       cause an SQLException error, "Result is from UPDATE".
       (Bug#25009: http://bugs.mysql.com/25009)

     * Specifying US-ASCII as the character set in a connection to a
       MySQL 4.1 or newer server does not map correctly.
       (Bug#24840: http://bugs.mysql.com/24840)

     * Using DatabaseMetaData.getSQLKeywords() does not return a all
       of the of the reserved keywords for the current MySQL version.
       Current implementation returns the list of reserved words for
       MySQL 5.1, and does not distinguish between versions.
       (Bug#24794: http://bugs.mysql.com/24794)

     * Calling Statement.cancel() could result in a Null Pointer
       Exception (NPE). (Bug#24721: http://bugs.mysql.com/24721)

     * Using setFetchSize() breaks prepared SHOW
       (http://dev.mysql.com/doc/refman/5.0/en/show.html) and other
       commands. (Bug#24360: http://bugs.mysql.com/24360)

     * Calendars and timezones are now lazily instantiated when
       required. (Bug#24351: http://bugs.mysql.com/24351)

     * Using DATETIME
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html) columns
       would result in time shifts when useServerPrepStmts was true.
       The reason was due to different behavior when using
       client-side compared to server-side prepared statements and
       the useJDBCCompliantTimezoneShift option. This is now fixed if
       moving from server-side prepared statements to client-side
       prepared statements by setting useSSPSCompatibleTimezoneShift
       to true, as the driver can't tell if this is a new deployment
       that never used server-side prepared statements, or if it is
       an existing deployment that is switching to client-side
       prepared statements from server-side prepared statements.
       (Bug#24344: http://bugs.mysql.com/24344)

     * Connector/J now returns a better error message when server
       doesn't return enough information to determine stored
       procedure/function parameter types.
       (Bug#24065: http://bugs.mysql.com/24065)

     * A connection error would occur when connecting to a MySQL
       server with certain character sets. Some collations/character
       sets reported as "unknown" (specifically cias variants of
       existing character sets), and inability to override the
       detected server character set.
       (Bug#23645: http://bugs.mysql.com/23645)

     * Inconsistency between getSchemas and INFORMATION_SCHEMA.
       (Bug#23304: http://bugs.mysql.com/23304)

     * DatabaseMetaData.getSchemas() doesn't return a TABLE_CATALOG
       column. (Bug#23303: http://bugs.mysql.com/23303)

     * When using a JDBC connection URL that is malformed, the
       NonRegisteringDriver.getPropertyInfo method will throw a Null
       Pointer Exception (NPE).
       (Bug#22628: http://bugs.mysql.com/22628)

     * Some exceptions thrown out of StandardSocketFactory were
       needlessly wrapped, obscuring their true cause, especially
       when using socket timeouts.
       (Bug#21480: http://bugs.mysql.com/21480)

     * When using a server-side prepared statement the driver would
       send timestamps to the server using nanoseconds instead of
       milliseconds. (Bug#21438: http://bugs.mysql.com/21438)

     * When using server-side prepared statements and timestamp
       columns, value would be incorrectly populated (with
       nanoseconds, not microseconds).
       (Bug#21438: http://bugs.mysql.com/21438)

     * ParameterMetaData throws NullPointerException when prepared
       SQL has a syntax error. Added generateSimpleParameterMetadata
       configuration property, which when set to true will generate
       metadata reflecting VARCHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html) for every
       parameter (the default is false, which will cause an exception
       to be thrown if no parameter metadata for the statement is
       actually available). (Bug#21267: http://bugs.mysql.com/21267)

     * Fixed an issue where XADataSources couldn't be bound into
       JNDI, as the DataSourceFactory didn't know how to create
       instances of them.

   Other changes:

     * Avoid static synchronized code in JVM class libraries for
       dealing with default timezones.

     * Performance enhancement of initial character set
       configuration, driver will only send commands required to
       configure connection character set session variables if the
       current values on the server do not match what is required.

     * Re-worked stored procedure parameter parser to be more robust.
       Driver no longer requires BEGIN in stored procedure
       definition, but does have requirement that if a stored
       function begins with a label directly after the "returns"
       clause, that the label is not a quoted identifier.

     * Throw exceptions encountered during timeout to thread calling
       Statement.execute*(), rather than RuntimeException.

     * Changed cached result set metadata (when using
       cacheResultSetMetadata=true) to be cached per-connection
       rather than per-statement as previously implemented.

     * Reverted back to internal character conversion routines for
       single-byte character sets, as the ones internal to the JVM
       are using much more CPU time than our internal implementation.

     * When extracting foreign key information from SHOW CREATE TABLE
       (http://dev.mysql.com/doc/refman/5.0/en/show-create-table.html
       ) in DatabaseMetaData, ignore exceptions relating to tables
       being missing (which could happen for cross-reference or
       imported-key requests, as the list of tables is generated
       first, then iterated).

     * Fixed some Null Pointer Exceptions (NPEs) when cached metadata
       was used with UpdatableResultSets.

     * Take localSocketAddress property into account when creating
       instances of CommunicationsException when the underyling
       exception is a java.net.BindException, so that a friendlier
       error message is given with a little internal diagnostics.

     * Fixed cases where ServerPreparedStatements weren't using
       cached metadata when cacheResultSetMetadata=true was used.

     * Use a java.util.TreeMap to map column names to ordinal indexes
       for ResultSet.findColumn() instead of a HashMap. This allows
       us to have case-insensitive lookups (required by the JDBC
       specification) without resorting to the many transient object
       instances needed to support this requirement with a normal
       HashMap with either case-adjusted keys, or case-insensitive
       keys. (In the worst case scenario for lookups of a 1000 column
       result set, TreeMaps are about half as fast wall-clock time as
       a HashMap, however in normal applications their use gives many
       orders of magnitude reduction in transient object instance
       creation which pays off later for CPU usage in garbage
       collection).

     * When using cached metadata, skip field-level metadata packets
       coming from the server, rather than reading them and
       discarding them without creating com.mysql.jdbc.Field
       instances.

A.2.5. Changes in MySQL Connector/J 5.0.4 (20 October 2006)

   Bugs fixed:

     * DBMD.getColumns() does not return expected COLUMN_SIZE for the
       SET type, now returns length of largest possible set
       disregarding whitespace or the "," delimitters to be
       consistent with the ODBC driver.
       (Bug#22613: http://bugs.mysql.com/22613)

     * Added new _ci collations to CharsetMapping - utf8_unicode_ci
       not working. (Bug#22456: http://bugs.mysql.com/22456)

     * Driver was using milliseconds for Statement.setQueryTimeout()
       when specification says argument is to be in seconds.
       (Bug#22359: http://bugs.mysql.com/22359)

     * Workaround for server crash when calling stored procedures via
       a server-side prepared statement (driver now detects
       prepare(stored procedure) and substitutes client-side prepared
       statement). (Bug#22297: http://bugs.mysql.com/22297)

     * Driver issues truncation on write exception when it shouldn't
       (due to sending big decimal incorrectly to server with
       server-side prepared statement).
       (Bug#22290: http://bugs.mysql.com/22290)

     * Newlines causing whitespace to span confuse procedure parser
       when getting parameter metadata for stored procedures.
       (Bug#22024: http://bugs.mysql.com/22024)

     * When using information_schema for metadata, COLUMN_SIZE for
       getColumns() is not clamped to range of java.lang.Integer as
       is the case when not using information_schema, thus leading to
       a truncation exception that isn't present when not using
       information_schema. (Bug#21544: http://bugs.mysql.com/21544)

     * Column names don't match metadata in cases where server
       doesn't return original column names (column functions) thus
       breaking compatibility with applications that expect 1-1
       mappings between findColumn() and rsmd.getColumnName(),
       usually manifests itself as "Can't find column ('')"
       exceptions. (Bug#21379: http://bugs.mysql.com/21379)

     * Driver now sends numeric 1 or 0 for client-prepared statement
       setBoolean() calls instead of '1' or '0'.

     * Fixed configuration property jdbcCompliantTruncation was not
       being used for reads of result set values.

     * DatabaseMetaData correctly reports true for supportsCatalog*()
       methods.

     * Driver now supports {call sp} (without "()" if procedure has
       no arguments).

A.2.6. Changes in MySQL Connector/J 5.0.3 (26 July 2006 beta)

   Functionality added or changed:

     * Added configuration option noAccessToProcedureBodies which
       will cause the driver to create basic parameter metadata for
       CallableStatements when the user does not have access to
       procedure bodies via SHOW CREATE PROCEDURE
       (http://dev.mysql.com/doc/refman/5.0/en/show-create-procedure.
       html) or selecting from mysql.proc instead of throwing an
       exception. The default value for this option is false

   Bugs fixed:

     * Fixed Statement.cancel() causes NullPointerException if
       underlying connection has been closed due to server failure.
       (Bug#20650: http://bugs.mysql.com/20650)

     * If the connection to the server has been closed due to a
       server failure, then the cleanup process will call
       Statement.cancel(), triggering a NullPointerException, even
       though there is no active connection.
       (Bug#20650: http://bugs.mysql.com/20650)

A.2.7. Changes in MySQL Connector/J 5.0.2 (11 July 2006)

   Bugs fixed:

     * MysqlXaConnection.recover(int flags) now allows combinations
       of XAResource.TMSTARTRSCAN and TMENDRSCAN. To simulate the
       "scanning" nature of the interface, we return all prepared
       XIDs for TMSTARTRSCAN, and no new XIDs for calls with
       TMNOFLAGS, or TMENDRSCAN when not in combination with
       TMSTARTRSCAN. This change was made for API compliance, as well
       as integration with IBM WebSphere's transaction manager.
       (Bug#20242: http://bugs.mysql.com/20242)

     * Fixed MysqlValidConnectionChecker for JBoss doesn't work with
       MySQLXADataSources. (Bug#20242: http://bugs.mysql.com/20242)

     * Added connection/datasource property
       pinGlobalTxToPhysicalConnection (defaults to false). When set
       to true, when using XAConnections, the driver ensures that
       operations on a given XID are always routed to the same
       physical connection. This allows the XAConnection to support
       XA START ... JOIN after XA END
       (http://dev.mysql.com/doc/refman/5.0/en/xa-statements.html)
       has been called, and is also a workaround for transaction
       managers that don't maintain thread affinity for a global
       transaction (most either always maintain thread affinity, or
       have it as a configuration option).
       (Bug#20242: http://bugs.mysql.com/20242)

     * Better caching of character set converters (per-connection) to
       remove a bottleneck for multibyte character sets.
       (Bug#20242: http://bugs.mysql.com/20242)

     * Fixed ConnectionProperties (and thus some subclasses) are not
       serializable, even though some J2EE containers expect them to
       be. (Bug#19169: http://bugs.mysql.com/19169)

     * Fixed driver fails on non-ASCII platforms. The driver was
       assuming that the platform character set would be a superset
       of MySQL's latin1 when doing the handshake for authentication,
       and when reading error messages. We now use Cp1252 for all
       strings sent to the server during the handshake phase, and a
       hard-coded mapping of the language
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_language) systtem variable to the character set
       that is used for error messages.
       (Bug#18086: http://bugs.mysql.com/18086)

     * Fixed can't use XAConnection for local transactions when no
       global transaction is in progress.
       (Bug#17401: http://bugs.mysql.com/17401)

A.2.8. Changes in MySQL Connector/J 5.0.1 (Not Released)

   Not released due to a packaging error

A.2.9. Changes in MySQL Connector/J 5.0.0 (22 December 2005)

   Bugs fixed:

     * Added support for Connector/MXJ integration via url
       subprotocol jdbc:mysql:mxj://....
       (Bug#14729: http://bugs.mysql.com/14729)

     * Idle timeouts cause XAConnections to whine about rolling
       themselves back. (Bug#14729: http://bugs.mysql.com/14729)

     * When fix for Bug#14562: http://bugs.mysql.com/14562 was merged
       from 3.1.12, added functionality for CallableStatement's
       parameter metadata to return correct information for
       .getParameterClassName().
       (Bug#14729: http://bugs.mysql.com/14729)

     * Added service-provider entry to
       META-INF/services/java.sql.Driver for JDBC-4.0 support.
       (Bug#14729: http://bugs.mysql.com/14729)

     * Fuller synchronization of Connection to avoid deadlocks when
       using multithreaded frameworks that multithread a single
       connection (usually not recommended, but the JDBC spec allows
       it anyways), part of fix to
       Bug#14972: http://bugs.mysql.com/14972).
       (Bug#14729: http://bugs.mysql.com/14729)

     * Moved all SQLException constructor usage to a factory in
       SQLError (ground-work for JDBC-4.0 SQLState-based exception
       classes). (Bug#14729: http://bugs.mysql.com/14729)

     * Removed Java5-specific calls to BigDecimal constructor (when
       result set value is '', (int)0 was being used as an argument
       indirectly via method return value. This signature doesn't
       exist prior to Java5.)
       (Bug#14729: http://bugs.mysql.com/14729)

     * Implementation of Statement.cancel() and
       Statement.setQueryTimeout(). Both require MySQL-5.0.0 or newer
       server, require a separate connection to issue the KILL QUERY
       (http://dev.mysql.com/doc/refman/5.0/en/kill.html) statement,
       and in the case of setQueryTimeout() creates an additional
       thread to handle the timeout functionality.
       Note: Failures to cancel the statement for setQueryTimeout()
       may manifest themselves as RuntimeExceptions rather than
       failing silently, as there is currently no way to unblock the
       thread that is executing the query being cancelled due to
       timeout expiration and have it throw the exception instead.
       (Bug#14729: http://bugs.mysql.com/14729)

     * Return "[VAR]BINARY" for RSMD.getColumnTypeName() when that is
       actually the type, and it can be distinguished (MySQL-4.1 and
       newer). (Bug#14729: http://bugs.mysql.com/14729)

     * Attempt detection of the MySQL type BINARY
       (http://dev.mysql.com/doc/refman/5.0/en/binary-varbinary.html)
       (it is an alias, so this isn't always reliable), and use the
       java.sql.Types.BINARY type mapping for it.

     * Added unit tests for XADatasource, as well as friendlier
       exceptions for XA failures compared to the "stock" XAException
       (which has no messages).

     * If the connection useTimezone is set to true, then also
       respect time zone conversions in escape-processed string
       literals (for example, "{ts ...}" and "{t ...}").

     * Don't allow .setAutoCommit(true), or .commit() or .rollback()
       on an XA-managed connection as per the JDBC specification.

     * XADataSource implemented (ported from 3.2 branch which won't
       be released as a product). Use
       com.mysql.jdbc.jdbc2.optional.MysqlXADataSource as your
       datasource class name in your application server to utilize XA
       transactions in MySQL-5.0.10 and newer.

     * Moved -bin-g.jar file into separate debug subdirectory to
       avoid confusion.

     * Return original column name for RSMD.getColumnName() if the
       column was aliased, alias name for .getColumnLabel() (if
       aliased), and original table name for .getTableName(). Note
       this only works for MySQL-4.1 and newer, as older servers
       don't make this information available to clients.

     * Setting useJDBCCompliantTimezoneShift=true (it is not the
       default) causes the driver to use GMT for all TIMESTAMP
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html)/DATETIM
       E (http://dev.mysql.com/doc/refman/5.0/en/datetime.html) time
       zones, and the current VM time zone for any other type that
       refers to time zones. This feature can not be used when
       useTimezone=true to convert between server and client time
       zones.

     * PreparedStatement.setString() didn't work correctly when
       sql_mode
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_sql_mode) on server contained
       NO_BACKSLASH_ESCAPES
       (http://dev.mysql.com/doc/refman/5.0/en/server-sql-mode.html#s
       qlmode_no_backslash_escapes) and no characters that needed
       escaping were present in the string.

     * Add one level of indirection of internal representation of
       CallableStatement parameter metadata to avoid class not found
       issues on JDK-1.3 for ParameterMetadata interface (which
       doesn't exist prior to JDBC-3.0).

A.3. Changes in MySQL Connector/J 3.1.x

A.3.1. Changes in MySQL Connector/J 3.1.15 (Not yet released)

   Important change: Due to a number of issues with the use of
   server-side prepared statements, Connector/J 5.0.5 has disabled
   their use by default. The disabling of server-side prepared
   statements does not affect the operation of the connector in any
   way.

   To enable server-side prepared statements you must add the
   following configuration property to your connector string:
useServerPrepStmts=true

   The default value of this property is false (that is, Connector/J
   does not use server-side prepared statements).

   Bugs fixed:

     * Specifying US-ASCII as the character set in a connection to a
       MySQL 4.1 or newer server does not map correctly.
       (Bug#24840: http://bugs.mysql.com/24840)

A.3.2. Changes in MySQL Connector/J 3.1.14 (10-19-2006)

   Bugs fixed:

     * Check and store value for continueBatchOnError property in
       constructor of Statements, rather than when executing batches,
       so that Connections closed out from underneath statements
       don't cause NullPointerExceptions when it is required to check
       this property. (Bug#22290: http://bugs.mysql.com/22290)

     * Fixed Bug#18258: http://bugs.mysql.com/18258 -
       DatabaseMetaData.getTables(), columns() with bad catalog
       parameter threw exception rather than return empty result set
       (as required by spec).
       (Bug#22290: http://bugs.mysql.com/22290)

     * Driver now sends numeric 1 or 0 for client-prepared statement
       setBoolean() calls instead of '1' or '0'.
       (Bug#22290: http://bugs.mysql.com/22290)

     * Fixed bug where driver would not advance to next host if
       roundRobinLoadBalance=true and the last host in the list is
       down. (Bug#22290: http://bugs.mysql.com/22290)

     * Driver issues truncation on write exception when it shouldn't
       (due to sending big decimal incorrectly to server with
       server-side prepared statement).
       (Bug#22290: http://bugs.mysql.com/22290)

     * Fixed bug when calling stored functions, where parameters
       weren't numbered correctly (first parameter is now the return
       value, subsequent parameters if specified start at index "2").
       (Bug#22290: http://bugs.mysql.com/22290)

     * Removed logger autodetection altogether, must now specify
       logger explicitly if you want to use a logger other than one
       that logs to STDERR. (Bug#21207: http://bugs.mysql.com/21207)

     * DDriver throws NPE when tracing prepared statements that have
       been closed (in asSQL()).
       (Bug#21207: http://bugs.mysql.com/21207)

     * ResultSet.getSomeInteger() doesn't work for BIT(>1).
       (Bug#21062: http://bugs.mysql.com/21062)

     * Escape of quotes in client-side prepared statements parsing
       not respected. Patch covers more than bug report, including
       NO_BACKSLASH_ESCAPES being set, and stacked quote characters
       forms of escaping (that is, '' or "").
       (Bug#20888: http://bugs.mysql.com/20888)

     * Fixed can't pool server-side prepared statements, exception
       raised when re-using them.
       (Bug#20687: http://bugs.mysql.com/20687)

     * Fixed Updatable result set that contains a BIT column fails
       when server-side prepared statements are used.
       (Bug#20485: http://bugs.mysql.com/20485)

     * Fixed updatable result set throws ClassCastException when
       there is row data and moveToInsertRow() is called.
       (Bug#20479: http://bugs.mysql.com/20479)

     * Fixed ResultSet.getShort() for UNSIGNED TINYINT returns
       incorrect values when using server-side prepared statements.
       (Bug#20306: http://bugs.mysql.com/20306)

     * ReplicationDriver does not always round-robin load balance
       depending on URL used for slaves list.
       (Bug#19993: http://bugs.mysql.com/19993)

     * Fixed calling toString() on ResultSetMetaData for
       driver-generated (that is, from DatabaseMetaData method calls,
       or from getGeneratedKeys()) result sets would raise a
       NullPointerException. (Bug#19993: http://bugs.mysql.com/19993)

     * Connection fails to localhost when using timeout and IPv6 is
       configured. (Bug#19726: http://bugs.mysql.com/19726)

     * ResultSet.getFloatFromString() can't retrieve values near
       Float.MIN/MAX_VALUE. (Bug#18880: http://bugs.mysql.com/18880)

     * Fixed memory leak with profileSQL=true.
       (Bug#16987: http://bugs.mysql.com/16987)

     * Fixed NullPointerException in MysqlDataSourceFactory due to
       Reference containing RefAddrs with null content.
       (Bug#16791: http://bugs.mysql.com/16791)

A.3.3. Changes in MySQL Connector/J 3.1.13 (26 May 2006)

   Bugs fixed:

     * Fixed PreparedStatement.setObject(int, Object, int) doesn't
       respect scale of BigDecimals.
       (Bug#19615: http://bugs.mysql.com/19615)

     * Fixed ResultSet.wasNull() returns incorrect value when
       extracting native string from server-side prepared statement
       generated result set. (Bug#19282: http://bugs.mysql.com/19282)

     * Fixed invalid classname returned for
       ResultSetMetaData.getColumnClassName() for BIGINT type.
       (Bug#19282: http://bugs.mysql.com/19282)

     * Fixed case where driver wasn't reading server status correctly
       when fetching server-side prepared statement rows, which in
       some cases could cause warning counts to be off, or multiple
       result sets to not be read off the wire.
       (Bug#19282: http://bugs.mysql.com/19282)

     * Fixed data truncation and getWarnings() only returns last
       warning in set. (Bug#18740: http://bugs.mysql.com/18740)

     * Fixed aliased column names where length of name > 251 are
       corrupted. (Bug#18554: http://bugs.mysql.com/18554)

     * Improved performance of retrieving BigDecimal, Time, Timestamp
       and Date values from server-side prepared statements by
       creating fewer short-lived instances of Strings when the
       native type is not an exact match for the requested type.
       (Bug#18496: http://bugs.mysql.com/18496)

     * Added performance feature, re-writing of batched executes for
       Statement.executeBatch() (for all DML statements) and
       PreparedStatement.executeBatch() (for INSERTs with VALUE
       clauses only). Enable by using "rewriteBatchedStatements=true"
       in your JDBC URL. (Bug#18041: http://bugs.mysql.com/18041)

     * Fixed issue where server-side prepared statements don't cause
       truncation exceptions to be thrown when truncation happens.
       (Bug#18041: http://bugs.mysql.com/18041)

     * Fixed CallableStatement.registerOutParameter() not working
       when some parameters pre-populated. Still waiting for feedback
       from JDBC experts group to determine what correct parameter
       count from getMetaData() should be, however.
       (Bug#17898: http://bugs.mysql.com/17898)

     * Fixed calling clearParameters() on a closed prepared statement
       causes NPE. (Bug#17587: http://bugs.mysql.com/17587)

     * Map "latin1" on MySQL server to CP1252 for MySQL > 4.1.0.
       (Bug#17587: http://bugs.mysql.com/17587)

     * Added additional accessor and mutator methods on
       ConnectionProperties so that DataSource users can use same
       naming as regular URL properties.
       (Bug#17587: http://bugs.mysql.com/17587)

     * Fixed ResultSet.wasNull() not always reset correctly for
       booleans when done via conversion for server-side prepared
       statements. (Bug#17450: http://bugs.mysql.com/17450)

     * Fixed Statement.getGeneratedKeys() throws NullPointerException
       when no query has been processed.
       (Bug#17099: http://bugs.mysql.com/17099)

     * Fixed updatable result set doesn't return AUTO_INCREMENT
       values for insertRow() when multiple column primary keys are
       used. (the driver was checking for the existence of
       single-column primary keys and an autoincrement value > 0
       instead of a straightforward isAutoIncrement() check).
       (Bug#16841: http://bugs.mysql.com/16841)

     * DBMD.getColumns() returns wrong type for BIT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html).
       (Bug#15854: http://bugs.mysql.com/15854)

     * lib-nodist directory missing from package breaks out-of-box
       build. (Bug#15676: http://bugs.mysql.com/15676)

     * Fixed issue with ReplicationConnection incorrectly copying
       state, doesn't transfer connection context correctly when
       transitioning between the same read-only states.
       (Bug#15570: http://bugs.mysql.com/15570)

     * No "dos" character set in MySQL > 4.1.0.
       (Bug#15544: http://bugs.mysql.com/15544)

     * INOUT parameter does not store IN value.
       (Bug#15464: http://bugs.mysql.com/15464)

     * PreparedStatement.setObject() serializes BigInteger as object,
       rather than sending as numeric value (and is thus not
       complementary to .getObject() on an UNSIGNED LONG type).
       (Bug#15383: http://bugs.mysql.com/15383)

     * Fixed issue where driver was unable to initialize character
       set mapping tables. Removed reliance on .properties files to
       hold this information, as it turns out to be too problematic
       to code around class loader hierarchies that change depending
       on how an application is deployed. Moved information back into
       the CharsetMapping class.
       (Bug#14938: http://bugs.mysql.com/14938)

     * Exception thrown for new decimal type when using updatable
       result sets. (Bug#14609: http://bugs.mysql.com/14609)

     * Driver now aware of fix for BIT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       type metadata that went into MySQL-5.0.21 for server not
       reporting length consistently .
       (Bug#13601: http://bugs.mysql.com/13601)

     * Added support for Apache Commons logging, use
       "com.mysql.jdbc.log.CommonsLogger" as the value for the
       "logger" configuration property.
       (Bug#13469: http://bugs.mysql.com/13469)

     * Fixed driver trying to call methods that don't exist on older
       and newer versions of Log4j. The fix is not trying to
       auto-detect presence of log4j, too many different incompatible
       versions out there in the wild to do this reliably.
       If you relied on autodetection before, you will need to add
       "logger=com.mysql.jdbc.log.Log4JLogger" to your JDBC URL to
       enable Log4J usage, or alternatively use the new
       "CommonsLogger" class to take care of this.
       (Bug#13469: http://bugs.mysql.com/13469)

     * LogFactory now prepends "com.mysql.jdbc.log" to log class name
       if it can't be found as-specified. This allows you to use
       "short names" for the built-in log factories, for example
       "logger=CommonsLogger" instead of
       "logger=com.mysql.jdbc.log.CommonsLogger".
       (Bug#13469: http://bugs.mysql.com/13469)

     * ResultSet.getShort() for UNSIGNED TINYINT returned wrong
       values. (Bug#11874: http://bugs.mysql.com/11874)

A.3.4. Changes in MySQL Connector/J 3.1.12 (30 November 2005)

   Bugs fixed:

     * Process escape tokens in Connection.prepareStatement(...). You
       can disable this behavior by setting the JDBC URL
       configuration property processEscapeCodesForPrepStmts to
       false. (Bug#15141: http://bugs.mysql.com/15141)

     * Usage advisor complains about unreferenced columns, even
       though they've been referenced.
       (Bug#15065: http://bugs.mysql.com/15065)

     * Driver incorrectly closes streams passed as arguments to
       PreparedStatements. Reverts to legacy behavior by setting the
       JDBC configuration property autoClosePStmtStreams to true
       (also included in the 3-0-Compat configuration "bundle").
       (Bug#15024: http://bugs.mysql.com/15024)

     * Deadlock while closing server-side prepared statements from
       multiple threads sharing one connection.
       (Bug#14972: http://bugs.mysql.com/14972)

     * Unable to initialize character set mapping tables (due to J2EE
       classloader differences).
       (Bug#14938: http://bugs.mysql.com/14938)

     * Escape processor replaces quote character in quoted string
       with string delimiter.
       (Bug#14909: http://bugs.mysql.com/14909)

     * DatabaseMetaData.getColumns() doesn't return TABLE_NAME
       correctly. (Bug#14815: http://bugs.mysql.com/14815)

     * storesMixedCaseIdentifiers() returns false
       (Bug#14562: http://bugs.mysql.com/14562)

     * storesLowerCaseIdentifiers() returns true
       (Bug#14562: http://bugs.mysql.com/14562)

     * storesMixedCaseQuotedIdentifiers() returns false
       (Bug#14562: http://bugs.mysql.com/14562)

     * storesMixedCaseQuotedIdentifiers() returns true
       (Bug#14562: http://bugs.mysql.com/14562)

     * If lower_case_table_names=0 (on server):

          + storesLowerCaseIdentifiers() returns false

          + storesLowerCaseQuotedIdentifiers() returns false

          + storesMixedCaseIdentifiers() returns true

          + storesMixedCaseQuotedIdentifiers() returns true

          + storesUpperCaseIdentifiers() returns false

          + storesUpperCaseQuotedIdentifiers() returns true
       (Bug#14562: http://bugs.mysql.com/14562)

     * storesUpperCaseIdentifiers() returns false
       (Bug#14562: http://bugs.mysql.com/14562)

     * storesUpperCaseQuotedIdentifiers() returns true
       (Bug#14562: http://bugs.mysql.com/14562)

     * If lower_case_table_names=1 (on server):

          + storesLowerCaseIdentifiers() returns true

          + storesLowerCaseQuotedIdentifiers() returns true

          + storesMixedCaseIdentifiers() returns false

          + storesMixedCaseQuotedIdentifiers() returns false

          + storesUpperCaseIdentifiers() returns false

          + storesUpperCaseQuotedIdentifiers() returns true
       (Bug#14562: http://bugs.mysql.com/14562)

     * storesLowerCaseQuotedIdentifiers() returns true
       (Bug#14562: http://bugs.mysql.com/14562)

     * Fixed DatabaseMetaData.stores*Identifiers():

          + If lower_case_table_names=0 (on server):
               o storesLowerCaseIdentifiers() returns false
               o storesLowerCaseQuotedIdentifiers() returns false
               o storesMixedCaseIdentifiers() returns true
               o storesMixedCaseQuotedIdentifiers() returns true
               o storesUpperCaseIdentifiers() returns false
               o storesUpperCaseQuotedIdentifiers() returns true

          + If lower_case_table_names=1 (on server):
               o storesLowerCaseIdentifiers() returns true
               o storesLowerCaseQuotedIdentifiers() returns true
               o storesMixedCaseIdentifiers() returns false
               o storesMixedCaseQuotedIdentifiers() returns false
               o storesUpperCaseIdentifiers() returns false
               o storesUpperCaseQuotedIdentifiers() returns true
       (Bug#14562: http://bugs.mysql.com/14562)

     * storesMixedCaseIdentifiers() returns true
       (Bug#14562: http://bugs.mysql.com/14562)

     * storesLowerCaseQuotedIdentifiers() returns false
       (Bug#14562: http://bugs.mysql.com/14562)

     * Java type conversion may be incorrect for MEDIUMINT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html).
       (Bug#14562: http://bugs.mysql.com/14562)

     * storesLowerCaseIdentifiers() returns false
       (Bug#14562: http://bugs.mysql.com/14562)

     * Added configuration property useGmtMillisForDatetimes which
       when set to true causes ResultSet.getDate(), .getTimestamp()
       to return correct millis-since GMT when .getTime() is called
       on the return value (currently default is false for legacy
       behavior). (Bug#14562: http://bugs.mysql.com/14562)

     * Extraneous sleep on autoReconnect.
       (Bug#13775: http://bugs.mysql.com/13775)

     * Reconnect during middle of executeBatch() should not occur if
       autoReconnect is enabled.
       (Bug#13255: http://bugs.mysql.com/13255)

     * maxQuerySizeToLog is not respected. Added logging of bound
       values for execute() phase of server-side prepared statements
       when profileSQL=true as well.
       (Bug#13048: http://bugs.mysql.com/13048)

     * OpenOffice expects DBMD.supportsIntegrityEnhancementFacility()
       to return true if foreign keys are supported by the
       datasource, even though this method also covers support for
       check constraints, which MySQL doesn't have. Setting the
       configuration property
       overrideSupportsIntegrityEnhancementFacility to true causes
       the driver to return true for this method.
       (Bug#12975: http://bugs.mysql.com/12975)

     * Added com.mysql.jdbc.testsuite.url.default system property to
       set default JDBC url for testsuite (to speed up bug resolution
       when I'm working in Eclipse).
       (Bug#12975: http://bugs.mysql.com/12975)

     * logSlowQueries should give better info.
       (Bug#12230: http://bugs.mysql.com/12230)

     * Don't increase timeout for failover/reconnect.
       (Bug#6577: http://bugs.mysql.com/6577)

     * Fixed client-side prepared statement bug with embedded ?
       characters inside quoted identifiers (it was recognized as a
       placeholder, when it was not).

     * Don't allow executeBatch() for CallableStatements with
       registered OUT/INOUT parameters (JDBC compliance).

     * Fall back to platform-encoding for URLDecoder.decode() when
       parsing driver URL properties if the platform doesn't have a
       two-argument version of this method.

A.3.5. Changes in MySQL Connector/J 3.1.11 (07 October 2005)

   Bugs fixed:

     * The configuration property sessionVariables now allows you to
       specify variables that start with the "@" sign.
       (Bug#13453: http://bugs.mysql.com/13453)

     * URL configuration parameters don't allow "&" or "=" in their
       values. The JDBC driver now parses configuration parameters as
       if they are encoded using the
       application/x-www-form-urlencoded format as specified by
       java.net.URLDecoder
       (http://java.sun.com/j2se/1.5.0/docs/api/java/net/URLDecoder.h
       tml).
       If the "%" character is present in a configuration property,
       it must now be represented as %25, which is the encoded form
       of "%" when using application/x-www-form-urlencoded encoding.
       (Bug#13453: http://bugs.mysql.com/13453)

     * Workaround for Bug#13374: http://bugs.mysql.com/13374:
       ResultSet.getStatement() on closed result set returns NULL (as
       per JDBC 4.0 spec, but not backward-compatible). Set the
       connection property retainStatementAfterResultSetClose to true
       to be able to retrieve a ResultSet's statement after the
       ResultSet has been closed via .getStatement() (the default is
       false, to be JDBC-compliant and to reduce the chance that code
       using JDBC leaks Statement instances).
       (Bug#13277: http://bugs.mysql.com/13277)

     * ResultSetMetaData from Statement.getGeneratedKeys() caused a
       NullPointerException to be thrown whenever a method that
       required a connection reference was called.
       (Bug#13277: http://bugs.mysql.com/13277)

     * Backport of VAR[BINARY|CHAR] [BINARY] types detection from 5.0
       branch. (Bug#13277: http://bugs.mysql.com/13277)

     * Fixed NullPointerException when converting catalog parameter
       in many DatabaseMetaDataMethods to byte[]s (for the result
       set) when the parameter is null. (null isn't technically
       allowed by the JDBC specification, but we've historically
       allowed it). (Bug#13277: http://bugs.mysql.com/13277)

     * Backport of Field class,
       ResultSetMetaData.getColumnClassName(), and
       ResultSet.getObject(int) changes from 5.0 branch to fix
       behavior surrounding VARCHAR BINARY/VARBINARY
       (http://dev.mysql.com/doc/refman/5.0/en/binary-varbinary.html)
       and related types. (Bug#13277: http://bugs.mysql.com/13277)

     * Read response in MysqlIO.sendFileToServer(), even if the local
       file can't be opened, otherwise next query issued will fail,
       because it is reading the response to the empty LOAD DATA
       INFILE (http://dev.mysql.com/doc/refman/5.0/en/load-data.html)
       packet sent to the server.
       (Bug#13277: http://bugs.mysql.com/13277)

     * When gatherPerfMetrics is enabled for servers older than
       4.1.0, a NullPointerException is thrown from the constructor
       of ResultSet if the query doesn't use any tables.
       (Bug#13043: http://bugs.mysql.com/13043)

     * java.sql.Types.OTHER returned for BINARY
       (http://dev.mysql.com/doc/refman/5.0/en/binary-varbinary.html)
       and VARBINARY
       (http://dev.mysql.com/doc/refman/5.0/en/binary-varbinary.html)
       columns when using DatabaseMetaData.getColumns().
       (Bug#12970: http://bugs.mysql.com/12970)

     * ServerPreparedStatement.getBinding() now checks if the
       statement is closed before attempting to reference the list of
       parameter bindings, to avoid throwing a NullPointerException.
       (Bug#12970: http://bugs.mysql.com/12970)

     * Tokenizer for = in URL properties was causing
       sessionVariables=.... to be parameterized incorrectly.
       (Bug#12753: http://bugs.mysql.com/12753)

     * cp1251 incorrectly mapped to win1251 for servers newer than
       4.0.x. (Bug#12752: http://bugs.mysql.com/12752)

     * getExportedKeys() (Bug#12541: http://bugs.mysql.com/12541)

     * Specifying a catalog works as stated in the API docs.
       (Bug#12541: http://bugs.mysql.com/12541)

     * Specifying NULL means that catalog will not be used to filter
       the results (thus all databases will be searched), unless
       you've set nullCatalogMeansCurrent=true in your JDBC URL
       properties. (Bug#12541: http://bugs.mysql.com/12541)

     * getIndexInfo() (Bug#12541: http://bugs.mysql.com/12541)

     * getProcedures() (and thus indirectly getProcedureColumns())
       (Bug#12541: http://bugs.mysql.com/12541)

     * getImportedKeys() (Bug#12541: http://bugs.mysql.com/12541)

     * Specifying "" means "current" catalog, even though this isn't
       quite JDBC spec compliant, it is there for legacy users.
       (Bug#12541: http://bugs.mysql.com/12541)

     * getCrossReference() (Bug#12541: http://bugs.mysql.com/12541)

     * Added Connection.isMasterConnection() for clients to be able
       to determine if a multi-host master/slave connection is
       connected to the first host in the list.
       (Bug#12541: http://bugs.mysql.com/12541)

     * getColumns() (Bug#12541: http://bugs.mysql.com/12541)

     * Handling of catalog argument in
       DatabaseMetaData.getIndexInfo(), which also means changes to
       the following methods in DatabaseMetaData:

          + getBestRowIdentifier()

          + getColumns()

          + getCrossReference()

          + getExportedKeys()

          + getImportedKeys()

          + getIndexInfo()

          + getPrimaryKeys()

          + getProcedures() (and thus indirectly
            getProcedureColumns())

          + getTables()
       The catalog argument in all of these methods now behaves in
       the following way:

          + Specifying NULL means that catalog will not be used to
            filter the results (thus all databases will be searched),
            unless you've set nullCatalogMeansCurrent=true in your
            JDBC URL properties.

          + Specifying "" means "current" catalog, even though this
            isn't quite JDBC spec compliant, it is there for legacy
            users.

          + Specifying a catalog works as stated in the API docs.

          + Made Connection.clientPrepare() available from "wrapped"
            connections in the jdbc2.optional package (connections
            built by ConnectionPoolDataSource instances).
       (Bug#12541: http://bugs.mysql.com/12541)

     * getBestRowIdentifier()
       (Bug#12541: http://bugs.mysql.com/12541)

     * Made Connection.clientPrepare() available from "wrapped"
       connections in the jdbc2.optional package (connections built
       by ConnectionPoolDataSource instances).
       (Bug#12541: http://bugs.mysql.com/12541)

     * getTables() (Bug#12541: http://bugs.mysql.com/12541)

     * getPrimaryKeys() (Bug#12541: http://bugs.mysql.com/12541)

     * Connection.prepareCall() is database name case-sensitive (on
       Windows systems). (Bug#12417: http://bugs.mysql.com/12417)

     * explainSlowQueries hangs with server-side prepared statements.
       (Bug#12229: http://bugs.mysql.com/12229)

     * Properties shared between master and slave with replication
       connection. (Bug#12218: http://bugs.mysql.com/12218)

     * Geometry types not handled with server-side prepared
       statements. (Bug#12104: http://bugs.mysql.com/12104)

     * maxPerformance.properties mis-spells "elideSetAutoCommits".
       (Bug#11976: http://bugs.mysql.com/11976)

     * ReplicationConnection won't switch to slave, throws "Catalog
       can't be null" exception.
       (Bug#11879: http://bugs.mysql.com/11879)

     * Pstmt.setObject(...., Types.BOOLEAN) throws exception.
       (Bug#11798: http://bugs.mysql.com/11798)

     * Escape tokenizer doesn't respect stacked single quotes for
       escapes. (Bug#11797: http://bugs.mysql.com/11797)

     * GEOMETRY type not recognized when using server-side prepared
       statements. (Bug#11797: http://bugs.mysql.com/11797)

     * Foreign key information that is quoted is parsed incorrectly
       when DatabaseMetaData methods use that information.
       (Bug#11781: http://bugs.mysql.com/11781)

     * The sendBlobChunkSize property is now clamped to
       max_allowed_packet
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_max_allowed_packet) with consideration of stream
       buffer size and packet headers to avoid PacketTooBigExceptions
       when max_allowed_packet
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_max_allowed_packet) is similar in size to the
       default sendBlobChunkSize which is 1M.
       (Bug#11781: http://bugs.mysql.com/11781)

     * CallableStatement.clearParameters() now clears resources
       associated with INOUT/OUTPUT parameters as well as INPUT
       parameters. (Bug#11781: http://bugs.mysql.com/11781)

     * Fixed regression caused by fix for
       Bug#11552: http://bugs.mysql.com/11552 that caused driver to
       return incorrect values for unsigned integers when those
       integers where within the range of the positive signed type.
       (Bug#11663: http://bugs.mysql.com/11663)

     * Moved source code to Subversion repository.
       (Bug#11663: http://bugs.mysql.com/11663)

     * Incorrect generation of testcase scripts for server-side
       prepared statements. (Bug#11663: http://bugs.mysql.com/11663)

     * Fixed statements generated for testcases missing ; for "plain"
       statements. (Bug#11629: http://bugs.mysql.com/11629)

     * Spurious ! on console when character encoding is utf8.
       (Bug#11629: http://bugs.mysql.com/11629)

     * StringUtils.getBytes() doesn't work when using multi-byte
       character encodings and a length in characters is specified.
       (Bug#11614: http://bugs.mysql.com/11614)

     * DBMD.storesLower/Mixed/UpperIdentifiers() reports incorrect
       values for servers deployed on Windows.
       (Bug#11575: http://bugs.mysql.com/11575)

     * Reworked Field class, *Buffer, and MysqlIO to be aware of
       field lengths > Integer.MAX_VALUE.
       (Bug#11498: http://bugs.mysql.com/11498)

     * Escape processor didn't honor strings demarcated with double
       quotes. (Bug#11498: http://bugs.mysql.com/11498)

     * Updated DBMD.supportsCorrelatedQueries() to return true for
       versions > 4.1, supportsGroupByUnrelated() to return true and
       getResultSetHoldability() to return HOLD_CURSORS_OVER_COMMIT.
       (Bug#11498: http://bugs.mysql.com/11498)

     * Lifted restriction of changing streaming parameters with
       server-side prepared statements. As long as all streaming
       parameters were set before execution, .clearParameters() does
       not have to be called. (due to limitation of client/server
       protocol, prepared statements can not reset individual stream
       data on the server side).
       (Bug#11498: http://bugs.mysql.com/11498)

     * ResultSet.moveToCurrentRow() fails to work when preceded by a
       call to ResultSet.moveToInsertRow().
       (Bug#11190: http://bugs.mysql.com/11190)

     * VARBINARY
       (http://dev.mysql.com/doc/refman/5.0/en/binary-varbinary.html)
       data corrupted when using server-side prepared statements and
       .setBytes(). (Bug#11115: http://bugs.mysql.com/11115)

     * Statement.getWarnings() fails with NPE if statement has been
       closed. (Bug#10630: http://bugs.mysql.com/10630)

     * Only get char[] from SQL in PreparedStatement.ParseInfo() when
       needed. (Bug#10630: http://bugs.mysql.com/10630)

A.3.6. Changes in MySQL Connector/J 3.1.10 (23 June 2005)

   Bugs fixed:

     * Initial implemention of ParameterMetadata for
       PreparedStatement.getParameterMetadata(). Only works fully for
       CallableStatements, as current server-side prepared statements
       return every parameter as a VARCHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html) type.

     * Fixed connecting without a database specified raised an
       exception in MysqlIO.changeDatabaseTo().

A.3.7. Changes in MySQL Connector/J 3.1.9 (22 June 2005)

   Bugs fixed:

     * Production package doesn't include JBoss integration classes.
       (Bug#11411: http://bugs.mysql.com/11411)

     * Removed nonsensical "costly type conversion" warnings when
       using usage advisor. (Bug#11411: http://bugs.mysql.com/11411)

     * Fixed PreparedStatement.setClob() not accepting null as a
       parameter. (Bug#11360: http://bugs.mysql.com/11360)

     * Connector/J dumping query into SQLException twice.
       (Bug#11360: http://bugs.mysql.com/11360)

     * autoReconnect ping causes exception on connection startup.
       (Bug#11259: http://bugs.mysql.com/11259)

     * Connection.setCatalog() is now aware of the
       useLocalSessionState configuration property, which when set to
       true will prevent the driver from sending USE ... to the
       server if the requested catalog is the same as the current
       catalog. (Bug#11115: http://bugs.mysql.com/11115)

     * 3-0-Compat --- Compatibility with Connector/J 3.0.x
       functionality (Bug#11115: http://bugs.mysql.com/11115)

     * maxPerformance --- maximum performance without being reckless
       (Bug#11115: http://bugs.mysql.com/11115)

     * solarisMaxPerformance --- maximum performance for Solaris,
       avoids syscalls where it can
       (Bug#11115: http://bugs.mysql.com/11115)

     * Added maintainTimeStats configuration property (defaults to
       true), which tells the driver whether or not to keep track of
       the last query time and the last successful packet sent to the
       server's time. If set to false, removes two syscalls per
       query. (Bug#11115: http://bugs.mysql.com/11115)

     * VARBINARY
       (http://dev.mysql.com/doc/refman/5.0/en/binary-varbinary.html)
       data corrupted when using server-side prepared statements and
       ResultSet.getBytes(). (Bug#11115: http://bugs.mysql.com/11115)

     * Added the following configuration bundles, use one or many via
       the useConfigs configuration property:

          + maxPerformance --- maximum performance without being
            reckless

          + solarisMaxPerformance --- maximum performance for
            Solaris, avoids syscalls where it can

          + 3-0-Compat --- Compatibility with Connector/J 3.0.x
            functionality
       (Bug#11115: http://bugs.mysql.com/11115)

     * Try to handle OutOfMemoryErrors more gracefully. Although not
       much can be done, they will in most cases close the connection
       they happened on so that further operations don't run into a
       connection in some unknown state. When an OOM has happened,
       any further operations on the connection will fail with a
       "Connection closed" exception that will also list the OOM
       exception as the reason for the implicit connection close
       event. (Bug#10850: http://bugs.mysql.com/10850)

     * Setting cachePrepStmts=true now causes the Connection to also
       cache the check the driver performs to determine if a prepared
       statement can be server-side or not, as well as caches
       server-side prepared statements for the lifetime of a
       connection. As before, the prepStmtCacheSize parameter
       controls the size of these caches.
       (Bug#10850: http://bugs.mysql.com/10850)

     * Don't send COM_RESET_STMT for each execution of a server-side
       prepared statement if it isn't required.
       (Bug#10850: http://bugs.mysql.com/10850)

     * 0-length streams not sent to server when using server-side
       prepared statements. (Bug#10850: http://bugs.mysql.com/10850)

     * Driver detects if you're running MySQL-5.0.7 or later, and
       does not scan for LIMIT ?[,?] in statements being prepared, as
       the server supports those types of queries now.
       (Bug#10850: http://bugs.mysql.com/10850)

     * Reorganized directory layout. Sources now are in src folder.
       Don't pollute parent directory when building, now output goes
       to ./build, distribution goes to ./dist.
       (Bug#10496: http://bugs.mysql.com/10496)

     * Added support/bug hunting feature that generates .sql test
       scripts to STDERR when autoGenerateTestcaseScript is set to
       true. (Bug#10496: http://bugs.mysql.com/10496)

     * SQLException is thrown when using property characterSetResults
       with cp932 or eucjpms.
       (Bug#10496: http://bugs.mysql.com/10496)

     * The datatype returned for TINYINT(1) columns when
       tinyInt1isBit=true (the default) can be switched between
       Types.BOOLEAN and Types.BIT using the new configuration
       property transformedBitIsBoolean, which defaults to false. If
       set to false (the default), DatabaseMetaData.getColumns() and
       ResultSetMetaData.getColumnType() will return Types.BOOLEAN
       for TINYINT(1) columns. If true, Types.BOOLEAN will be
       returned instead. Regardless of this configuration property,
       if tinyInt1isBit is enabled, columns with the type TINYINT(1)
       will be returned as java.lang.Boolean instances from
       ResultSet.getObject(...), and
       ResultSetMetaData.getColumnClassName() will return
       java.lang.Boolean. (Bug#10485: http://bugs.mysql.com/10485)

     * SQLException thrown when retrieving YEAR(2) with
       ResultSet.getString(). The driver will now always treat YEAR
       (http://dev.mysql.com/doc/refman/5.0/en/year.html) types as
       java.sql.Dates and return the correct values for getString().
       Alternatively, the yearIsDateType connection property can be
       set to false and the values will be treated as SHORTs.
       (Bug#10485: http://bugs.mysql.com/10485)

     * Driver doesn't support {?=CALL(...)} for calling stored
       functions. This involved adding support for function retrieval
       to DatabaseMetaData.getProcedures() and getProcedureColumns()
       as well. (Bug#10310: http://bugs.mysql.com/10310)

     * Unsigned SMALLINT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       treated as signed for ResultSet.getInt(), fixed all cases for
       UNSIGNED integer values and server-side prepared statements,
       as well as ResultSet.getObject() for UNSIGNED TINYINT.
       (Bug#10156: http://bugs.mysql.com/10156)

     * Made ServerPreparedStatement.asSql() work correctly so
       auto-explain functionality would work with server-side
       prepared statements. (Bug#10155: http://bugs.mysql.com/10155)

     * Double quotes not recognized when parsing client-side prepared
       statements. (Bug#10155: http://bugs.mysql.com/10155)

     * Made JDBC2-compliant wrappers public in order to allow access
       to vendor extensions. (Bug#10155: http://bugs.mysql.com/10155)

     * DatabaseMetaData.supportsMultipleOpenResults() now returns
       true. The driver has supported this for some time, DBMD just
       missed that fact. (Bug#10155: http://bugs.mysql.com/10155)

     * Cleaned up logging of profiler events, moved code to dump a
       profiler event as a string to com.mysql.jdbc.log.LogUtils so
       that third parties can use it.
       (Bug#10155: http://bugs.mysql.com/10155)

     * Made enableStreamingResults() visible on
       com.mysql.jdbc.jdbc2.optional.StatementWrapper.
       (Bug#10155: http://bugs.mysql.com/10155)

     * Actually write manifest file to correct place so it ends up in
       the binary jar file. (Bug#10144: http://bugs.mysql.com/10144)

     * Added createDatabaseIfNotExist property (default is false),
       which will cause the driver to ask the server to create the
       database specified in the URL if it doesn't exist. You must
       have the appropriate privileges for database creation for this
       to work. (Bug#10144: http://bugs.mysql.com/10144)

     * Memory leak in ServerPreparedStatement if serverPrepare()
       fails. (Bug#10144: http://bugs.mysql.com/10144)

     * com.mysql.jdbc.PreparedStatement.ParseInfo does unnecessary
       call to toCharArray(). (Bug#9064: http://bugs.mysql.com/9064)

     * Driver now correctly uses CP932 if available on the server for
       Windows-31J, CP932 and MS932 java encoding names, otherwise it
       resorts to SJIS, which is only a close approximation.
       Currently only MySQL-5.0.3 and newer (and MySQL-4.1.12 or .13,
       depending on when the character set gets backported) can
       reliably support any variant of CP932.

     * Overhaul of character set configuration, everything now lives
       in a properties file.

A.3.8. Changes in MySQL Connector/J 3.1.8 (14 April 2005)

   Bugs fixed:

     * Should accept null for catalog (meaning use current) in DBMD
       methods, even though it is not JDBC-compliant for legacy's
       sake. Disable by setting connection property
       nullCatalogMeansCurrent to false (which will be the default
       value in C/J 3.2.x). (Bug#9917: http://bugs.mysql.com/9917)

     * Fixed driver not returning true for -1 when
       ResultSet.getBoolean() was called on result sets returned from
       server-side prepared statements.
       (Bug#9778: http://bugs.mysql.com/9778)

     * Added a Manifest.MF file with implementation information to
       the .jar file. (Bug#9778: http://bugs.mysql.com/9778)

     * More tests in Field.isOpaqueBinary() to distinguish opaque
       binary (that is, fields with type CHAR(n) and CHARACTER SET
       BINARY) from output of various scalar and aggregate functions
       that return strings. (Bug#9778: http://bugs.mysql.com/9778)

     * DBMD.getTables() shouldn't return tables if views are asked
       for, even if the database version doesn't support views.
       (Bug#9778: http://bugs.mysql.com/9778)

     * Should accept null for name patterns in DBMD (meaning "%"),
       even though it isn't JDBC compliant, for legacy's sake.
       Disable by setting connection property
       nullNamePatternMatchesAll to false (which will be the default
       value in C/J 3.2.x). (Bug#9769: http://bugs.mysql.com/9769)

     * The performance metrics feature now gathers information about
       number of tables referenced in a SELECT.
       (Bug#9704: http://bugs.mysql.com/9704)

     * The logging system is now automatically configured. If the
       value has been set by the user, via the URL property logger or
       the system property com.mysql.jdbc.logger, then use that,
       otherwise, autodetect it using the following steps:

         1. Log4j, if it is available,

         2. Then JDK1.4 logging,

         3. Then fallback to our STDERR logging.
       (Bug#9704: http://bugs.mysql.com/9704)

     * Statement.getMoreResults() could throw NPE when existing
       result set was .close()d.
       (Bug#9704: http://bugs.mysql.com/9704)

     * Stored procedures with DECIMAL
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       parameters with storage specifications that contained "," in
       them would fail. (Bug#9682: http://bugs.mysql.com/9682)

     * PreparedStatement.setObject(int, Object, int type, int scale)
       now uses scale value for BigDecimal instances.
       (Bug#9682: http://bugs.mysql.com/9682)

     * Added support for the c3p0 connection pool's
       (http://c3p0.sf.net/) validation/connection checker interface
       which uses the lightweight COM_PING call to the server if
       available. To use it, configure your c3p0 connection pool's
       connectionTesterClassName property to use
       com.mysql.jdbc.integration.c3p0.MysqlConnectionTester.
       (Bug#9320: http://bugs.mysql.com/9320)

     * PreparedStatement.getMetaData() inserts blank row in database
       under certain conditions when not using server-side prepared
       statements. (Bug#9320: http://bugs.mysql.com/9320)

     * Better detection of LIMIT inside/outside of quoted strings so
       that the driver can more correctly determine whether a
       prepared statement can be prepared on the server or not.
       (Bug#9320: http://bugs.mysql.com/9320)

     * Connection.canHandleAsPreparedStatement() now makes "best
       effort" to distinguish LIMIT clauses with placeholders in them
       from ones without in order to have fewer false positives when
       generating work-arounds for statements the server cannot
       currently handle as server-side prepared statements.
       (Bug#9320: http://bugs.mysql.com/9320)

     * Fixed build.xml to not compile log4j logging if log4j not
       available. (Bug#9320: http://bugs.mysql.com/9320)

     * Added finalizers to ResultSet and Statement implementations to
       be JDBC spec-compliant, which requires that if not explicitly
       closed, these resources should be closed upon garbage
       collection. (Bug#9319: http://bugs.mysql.com/9319)

     * Stored procedures with same name in different databases
       confuse the driver when it tries to determine parameter
       counts/types. (Bug#9319: http://bugs.mysql.com/9319)

     * A continuation of Bug#8868: http://bugs.mysql.com/8868, where
       functions used in queries that should return nonstring types
       when resolved by temporary tables suddenly become opaque
       binary strings (work-around for server limitation). Also fixed
       fields with type of CHAR(n) CHARACTER SET BINARY to return
       correct/matching classes for RSMD.getColumnClassName() and
       ResultSet.getObject(). (Bug#9236: http://bugs.mysql.com/9236)

     * Cannot use UTF-8 for characterSetResults configuration
       property. (Bug#9206: http://bugs.mysql.com/9206)

     * PreparedStatement.addBatch() doesn't work with server-side
       prepared statements and streaming BINARY
       (http://dev.mysql.com/doc/refman/5.0/en/binary-varbinary.html)
       data. (Bug#9040: http://bugs.mysql.com/9040)

     * ServerPreparedStatements now correctly "stream" BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html)/CLOB data
       to the server. You can configure the threshold chunk size
       using the JDBC URL property blobSendChunkSize (the default is
       1MB). (Bug#8868: http://bugs.mysql.com/8868)

     * DATE_FORMAT()
       (http://dev.mysql.com/doc/refman/5.0/en/date-and-time-function
       s.html#function_date-format) queries returned as BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html)s from
       getObject(). (Bug#8868: http://bugs.mysql.com/8868)

     * Server-side session variables can be preset at connection time
       by passing them as a comma-delimited list for the connection
       property sessionVariables.
       (Bug#8868: http://bugs.mysql.com/8868)

     * BlobFromLocator now uses correct identifier quoting when
       generating prepared statements.
       (Bug#8868: http://bugs.mysql.com/8868)

     * Fixed regression in ping() for users using autoReconnect=true.
       (Bug#8868: http://bugs.mysql.com/8868)

     * Check for empty strings ('') when converting CHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html)/VARCHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html) column data
       to numbers, throw exception if emptyStringsConvertToZero
       configuration property is set to false (for
       backward-compatibility with 3.0, it is now set to true by
       default, but will most likely default to false in 3.2).
       (Bug#8803: http://bugs.mysql.com/8803)

     * DATA_TYPE column from DBMD.getBestRowIdentifier() causes
       ArrayIndexOutOfBoundsException when accessed (and in fact,
       didn't return any value).
       (Bug#8803: http://bugs.mysql.com/8803)

     * DBMD.supportsMixedCase*Identifiers() returns wrong value on
       servers running on case-sensitive file systems.
       (Bug#8800: http://bugs.mysql.com/8800)

     * DBMD.supportsResultSetConcurrency() not returning true for
       forward-only/read-only result sets (we obviously support
       this). (Bug#8792: http://bugs.mysql.com/8792)

     * Fixed ResultSet.getTime() on a NULL value for server-side
       prepared statements throws NPE.

     * Made Connection.ping() a public method.

     * Added support for new precision-math DECIMAL
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       type in MySQL 5.0.3 and up.

     * Fixed DatabaseMetaData.getTables() returning views when they
       were not asked for as one of the requested table types.

A.3.9. Changes in MySQL Connector/J 3.1.7 (18 February 2005)

   Bugs fixed:

     * PreparedStatements not creating streaming result sets.
       (Bug#8487: http://bugs.mysql.com/8487)

     * Don't pass NULL to String.valueOf() in
       ResultSet.getNativeConvertToString(), as it stringifies it
       (that is, returns null), which is not correct for the method
       in question. (Bug#8487: http://bugs.mysql.com/8487)

     * Fixed NPE in ResultSet.realClose() when using usage advisor
       and result set was already closed.
       (Bug#8428: http://bugs.mysql.com/8428)

     * ResultSet.getString() doesn't maintain format stored on
       server, bug fix only enabled when noDatetimeStringSync
       property is set to true (the default is false).
       (Bug#8428: http://bugs.mysql.com/8428)

     * Added support for BIT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       type in MySQL-5.0.3. The driver will treat BIT(1-8) as the
       JDBC standard BIT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       type (which maps to java.lang.Boolean), as the server does not
       currently send enough information to determine the size of a
       bitfield when < 9 bits are declared. BIT(>9) will be treated
       as VARBINARY
       (http://dev.mysql.com/doc/refman/5.0/en/binary-varbinary.html)
       , and will return byte[] when getObject() is called.
       (Bug#8424: http://bugs.mysql.com/8424)

     * Added useLocalSessionState configuration property, when set to
       true the JDBC driver trusts that the application is
       well-behaved and only sets autocommit and transaction
       isolation levels using the methods provided on
       java.sql.Connection, and therefore can manipulate these values
       in many cases without incurring round-trips to the database
       server. (Bug#8424: http://bugs.mysql.com/8424)

     * Added enableStreamingResults() to Statement for connection
       pool implementations that check Statement.setFetchSize() for
       specification-compliant values. Call
       Statement.setFetchSize(>=0) to disable the streaming results
       for that statement. (Bug#8424: http://bugs.mysql.com/8424)

     * ResultSet.getBigDecimal() throws exception when rounding would
       need to occur to set scale. The driver now chooses a rounding
       mode of "half up" if nonrounding BigDecimal.setScale() fails.
       (Bug#8424: http://bugs.mysql.com/8424)

     * Fixed synchronization issue with
       ServerPreparedStatement.serverPrepare() that could cause
       deadlocks/crashes if connection was shared between threads.
       (Bug#8096: http://bugs.mysql.com/8096)

     * Emulated locators corrupt binary data when using server-side
       prepared statements. (Bug#8096: http://bugs.mysql.com/8096)

     * Infinite recursion when "falling back" to master in failover
       configuration. (Bug#7952: http://bugs.mysql.com/7952)

     * Disable multi-statements (if enabled) for MySQL-4.1 versions
       prior to version 4.1.10 if the query cache is enabled, as the
       server returns wrong results in this configuration.
       (Bug#7952: http://bugs.mysql.com/7952)

     * Removed dontUnpackBinaryResults functionality, the driver now
       always stores results from server-side prepared statements as
       is from the server and unpacks them on demand.
       (Bug#7952: http://bugs.mysql.com/7952)

     * Fixed duplicated code in configureClientCharset() that
       prevented useOldUTF8Behavior=true from working properly.
       (Bug#7952: http://bugs.mysql.com/7952)

     * Added holdResultsOpenOverStatementClose property (default is
       false), that keeps result sets open over statement.close() or
       new execution on same statement (suggested by Kevin Burton).
       (Bug#7715: http://bugs.mysql.com/7715)

     * Detect new sql_mode
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_sql_mode) variable in string form (it used to be
       integer) and adjust quoting method for strings appropriately.
       (Bug#7715: http://bugs.mysql.com/7715)

     * Timestamps converted incorrectly to strings with server-side
       prepared statements and updatable result sets.
       (Bug#7715: http://bugs.mysql.com/7715)

     * Timestamp key column data needed _binary stripped for
       UpdatableResultSet.refreshRow().
       (Bug#7686: http://bugs.mysql.com/7686)

     * Choose correct "direction" to apply time adjustments when both
       client and server are in GMT time zone when using
       ResultSet.get(..., cal) and PreparedStatement.set(...., cal).
       (Bug#4718: http://bugs.mysql.com/4718)

     * Remove _binary introducer from parameters used as in/out
       parameters in CallableStatement.
       (Bug#4718: http://bugs.mysql.com/4718)

     * Always return byte[]s for output parameters registered as
       *BINARY. (Bug#4718: http://bugs.mysql.com/4718)

     * By default, the driver now scans SQL you are preparing via all
       variants of Connection.prepareStatement() to determine if it
       is a supported type of statement to prepare on the server
       side, and if it is not supported by the server, it instead
       prepares it as a client-side emulated prepared statement. You
       can disable this by passing emulateUnsupportedPstmts=false in
       your JDBC URL. (Bug#4718: http://bugs.mysql.com/4718)

     * Added dontTrackOpenResources option (default is false, to be
       JDBC compliant), which helps with memory use for
       nonwell-behaved apps (that is, applications that don't close
       Statement objects when they should).
       (Bug#4718: http://bugs.mysql.com/4718)

     * Send correct value for "boolean" true to server for
       PreparedStatement.setObject(n, "true", Types.BIT).
       (Bug#4718: http://bugs.mysql.com/4718)

     * Fixed bug with Connection not caching statements from
       prepareStatement() when the statement wasn't a server-side
       prepared statement. (Bug#4718: http://bugs.mysql.com/4718)

A.3.10. Changes in MySQL Connector/J 3.1.6 (23 December 2004)

   Bugs fixed:

     * DBMD.getProcedures() doesn't respect catalog parameter.
       (Bug#7026: http://bugs.mysql.com/7026)

     * Fixed hang on SocketInputStream.read() with
       Statement.setMaxRows() and multiple result sets when driver
       has to truncate result set directly, rather than tacking a
       LIMIT n on the end of it.

A.3.11. Changes in MySQL Connector/J 3.1.5 (02 December 2004)

   Bugs fixed:

     * Use 1MB packet for sending file for LOAD DATA LOCAL INFILE
       (http://dev.mysql.com/doc/refman/5.0/en/load-data.html) if
       that is < max_allowed_packet
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_max_allowed_packet) on server.
       (Bug#6537: http://bugs.mysql.com/6537)

     * SUM() on DECIMAL
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       with server-side prepared statement ignores scale if
       zero-padding is needed (this ends up being due to conversion
       to DOUBLE
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html) by
       server, which when converted to a string to parse into
       BigDecimal, loses all "padding" zeros).
       (Bug#6537: http://bugs.mysql.com/6537)

     * Use DatabaseMetaData.getIdentifierQuoteString() when building
       DBMD queries. (Bug#6537: http://bugs.mysql.com/6537)

     * Use our own implementation of buffered input streams to get
       around blocking behavior of java.io.BufferedInputStream.
       Disable this with useReadAheadInput=false.
       (Bug#6399: http://bugs.mysql.com/6399)

     * Make auto-deserialization of java.lang.Objects stored in BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) columns
       configurable via autoDeserialize property (defaults to false).
       (Bug#6399: http://bugs.mysql.com/6399)

     * ResultSetMetaData.getColumnDisplaySize() returns incorrect
       values for multi-byte charsets.
       (Bug#6399: http://bugs.mysql.com/6399)

     * Re-work Field.isOpaqueBinary() to detect CHAR(n) CHARACTER SET
       BINARY to support fixed-length binary fields for
       ResultSet.getObject(). (Bug#6399: http://bugs.mysql.com/6399)

     * Failing to connect to the server when one of the addresses for
       the given host name is IPV6 (which the server does not yet
       bind on). The driver now loops through all IP addresses for a
       given host, and stops on the first one that accepts() a
       socket.connect(). (Bug#6348: http://bugs.mysql.com/6348)

     * Removed unwanted new Throwable() in ResultSet constructor due
       to bad merge (caused a new object instance that was never used
       for every result set created). Found while profiling for
       Bug#6359: http://bugs.mysql.com/6359.
       (Bug#6225: http://bugs.mysql.com/6225)

     * ServerSidePreparedStatement allocating short-lived objects
       unnecessarily. (Bug#6225: http://bugs.mysql.com/6225)

     * Use null-safe-equals for key comparisons in updatable result
       sets. (Bug#6225: http://bugs.mysql.com/6225)

     * Fixed too-early creation of StringBuffer in
       EscapeProcessor.escapeSQL(), also return String when escaping
       not needed (to avoid unnecessary object allocations). Found
       while profiling for Bug#6359: http://bugs.mysql.com/6359.
       (Bug#6225: http://bugs.mysql.com/6225)

     * UNSIGNED BIGINT unpacked incorrectly from server-side prepared
       statement result sets. (Bug#5729: http://bugs.mysql.com/5729)

     * Added experimental configuration property
       dontUnpackBinaryResults, which delays unpacking binary result
       set values until they're asked for, and only creates object
       instances for nonnumerical values (it is set to false by
       default). For some usecase/jvm combinations, this is
       friendlier on the garbage collector.
       (Bug#5706: http://bugs.mysql.com/5706)

     * Don't throw exceptions for Connection.releaseSavepoint().
       (Bug#5706: http://bugs.mysql.com/5706)

     * Inefficient detection of pre-existing string instances in
       ResultSet.getNativeString().
       (Bug#5706: http://bugs.mysql.com/5706)

     * Use a per-session Calendar instance by default when decoding
       dates from ServerPreparedStatements (set to old, less
       performant behavior by setting property
       dynamicCalendars=true). (Bug#5706: http://bugs.mysql.com/5706)

     * Fixed batched updates with server prepared statements weren't
       looking if the types had changed for a given batched set of
       parameters compared to the previous set, causing the server to
       return the error "Wrong arguments to mysql_stmt_execute()".
       (Bug#5235: http://bugs.mysql.com/5235)

     * Handle case when string representation of timestamp contains
       trailing "." with no numbers following it.
       (Bug#5235: http://bugs.mysql.com/5235)

     * Server-side prepared statements did not honor
       zeroDateTimeBehavior property, and would cause class-cast
       exceptions when using ResultSet.getObject(), as the all-zero
       string was always returned.
       (Bug#5235: http://bugs.mysql.com/5235)

     * Fix comparisons made between string constants and dynamic
       strings that are converted with either toUpperCase() or
       toLowerCase() to use Locale.ENGLISH, as some locales
       "override" case rules for English. Also use
       StringUtils.indexOfIgnoreCase() instead of
       .toUpperCase().indexOf(), avoids creating a very short-lived
       transient String instance.

A.3.12. Changes in MySQL Connector/J 3.1.4 (04 September 2004)

   Bugs fixed:

     * Fixed ServerPreparedStatement to read prepared statement
       metadata off the wire, even though it is currently a
       placeholder instead of using MysqlIO.clearInputStream() which
       didn't work at various times because data wasn't available to
       read from the server yet. This fixes sporadic errors users
       were having with ServerPreparedStatements throwing
       ArrayIndexOutOfBoundExceptions.
       (Bug#5032: http://bugs.mysql.com/5032)

     * Added three ways to deal with all-zero datetimes when reading
       them from a ResultSet: exception (the default), which throws
       an SQLException with an SQLState of S1009; convertToNull,
       which returns NULL instead of the date; and round, which
       rounds the date to the nearest closest value which is
       '0001-01-01'. (Bug#5032: http://bugs.mysql.com/5032)

     * The driver is more strict about truncation of numerics on
       ResultSet.get*(), and will throw an SQLException when
       truncation is detected. You can disable this by setting
       jdbcCompliantTruncation to false (it is enabled by default, as
       this functionality is required for JDBC compliance).
       (Bug#5032: http://bugs.mysql.com/5032)

     * You can now use URLs in LOAD DATA LOCAL INFILE
       (http://dev.mysql.com/doc/refman/5.0/en/load-data.html)
       statements, and the driver will use Java's built-in handlers
       for retreiving the data and sending it to the server. This
       feature is not enabled by default, you must set the
       allowUrlInLocalInfile connection property to true.
       (Bug#5032: http://bugs.mysql.com/5032)

     * ResultSet.getObject() doesn't return type Boolean for
       pseudo-bit types from prepared statements on 4.1.x (shortcut
       for avoiding extra type conversion when using binary-encoded
       result sets obscured test in getObject() for "pseudo" bit
       type). (Bug#5032: http://bugs.mysql.com/5032)

     * Use com.mysql.jdbc.Message's classloader when loading resource
       bundle, should fix sporadic issues when the caller's
       classloader can't locate the resource bundle.
       (Bug#5032: http://bugs.mysql.com/5032)

     * ServerPreparedStatements dealing with return of DECIMAL
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       type don't work. (Bug#5012: http://bugs.mysql.com/5012)

     * Track packet sequence numbers if enablePacketDebug=true, and
       throw an exception if packets received out-of-order.
       (Bug#4689: http://bugs.mysql.com/4689)

     * ResultSet.wasNull() does not work for primatives if a previous
       null was returned. (Bug#4689: http://bugs.mysql.com/4689)

     * Optimized integer number parsing, enable "old" slower integer
       parsing using JDK classes via useFastIntParsing=false
       property. (Bug#4642: http://bugs.mysql.com/4642)

     * Added useOnlyServerErrorMessages property, which causes
       message text in exceptions generated by the server to only
       contain the text sent by the server (as opposed to the
       SQLState's "standard" description, followed by the server's
       error message). This property is set to true by default.
       (Bug#4642: http://bugs.mysql.com/4642)

     * ServerPreparedStatement.execute*() sometimes threw
       ArrayIndexOutOfBoundsException when unpacking field metadata.
       (Bug#4642: http://bugs.mysql.com/4642)

     * Connector/J 3.1.3 beta does not handle integers correctly
       (caused by changes to support unsigned reads in
       Buffer.readInt() -> Buffer.readShort()).
       (Bug#4510: http://bugs.mysql.com/4510)

     * Added support in DatabaseMetaData.getTables() and
       getTableTypes() for views, which are now available in MySQL
       server 5.0.x. (Bug#4510: http://bugs.mysql.com/4510)

     * ResultSet.getObject() returns wrong type for strings when
       using prepared statements.
       (Bug#4482: http://bugs.mysql.com/4482)

     * Calling MysqlPooledConnection.close() twice (even though an
       application error), caused NPE. Fixed.
       (Bug#4482: http://bugs.mysql.com/4482)

A.3.13. Changes in MySQL Connector/J 3.1.3 (07 July 2004)

   Bugs fixed:

     * Support new time zone variables in MySQL-4.1.3 when
       useTimezone=true. (Bug#4311: http://bugs.mysql.com/4311)

     * Error in retrieval of mediumint column with prepared
       statements and binary protocol.
       (Bug#4311: http://bugs.mysql.com/4311)

     * Support for unsigned numerics as return types from prepared
       statements. This also causes a change in ResultSet.getObject()
       for the bigint unsigned type, which used to return BigDecimal
       instances, it now returns instances of java.lang.BigInteger.
       (Bug#4311: http://bugs.mysql.com/4311)

     * Externalized more messages (on-going effort).
       (Bug#4119: http://bugs.mysql.com/4119)

     * Null bitmask sent for server-side prepared statements was
       incorrect. (Bug#4119: http://bugs.mysql.com/4119)

     * Added constants for MySQL error numbers (publicly accessible,
       see com.mysql.jdbc.MysqlErrorNumbers), and the ability to
       generate the mappings of vendor error codes to SQLStates that
       the driver uses (for documentation purposes).
       (Bug#4119: http://bugs.mysql.com/4119)

     * Added packet debuging code (see the enablePacketDebug property
       documentation). (Bug#4119: http://bugs.mysql.com/4119)

     * Use SQL Standard SQL states by default, unless
       useSqlStateCodes property is set to false.
       (Bug#4119: http://bugs.mysql.com/4119)

     * Mangle output parameter names for CallableStatements so they
       will not clash with user variable names.

     * Added support for INOUT parameters in CallableStatements.

A.3.14. Changes in MySQL Connector/J 3.1.2 (09 June 2004)

   Bugs fixed:

     * Don't enable server-side prepared statements for server
       version 5.0.0 or 5.0.1, as they aren't compatible with the
       '4.1.2+' style that the driver uses (the driver expects
       information to come back that isn't there, so it hangs).
       (Bug#3804: http://bugs.mysql.com/3804)

     * getWarnings() returns SQLWarning instead of DataTruncation.
       (Bug#3804: http://bugs.mysql.com/3804)

     * getProcedureColumns() doesn't work with wildcards for
       procedure name. (Bug#3540: http://bugs.mysql.com/3540)

     * getProcedures() does not return any procedures in result set.
       (Bug#3539: http://bugs.mysql.com/3539)

     * Fixed DatabaseMetaData.getProcedures() when run on MySQL-5.0.0
       (output of SHOW PROCEDURE STATUS
       (http://dev.mysql.com/doc/refman/5.0/en/show-procedure-status.
       html) changed between 5.0.0 and 5.0.1.
       (Bug#3520: http://bugs.mysql.com/3520)

     * Added connectionCollation property to cause driver to issue
       set collation_connection=... query on connection init if
       default collation for given charset is not appropriate.
       (Bug#3520: http://bugs.mysql.com/3520)

     * DBMD.getSQLStateType() returns incorrect value.
       (Bug#3520: http://bugs.mysql.com/3520)

     * Correctly map output parameters to position given in
       prepareCall() versus. order implied during
       registerOutParameter(). (Bug#3146: http://bugs.mysql.com/3146)

     * Cleaned up detection of server properties.
       (Bug#3146: http://bugs.mysql.com/3146)

     * Correctly detect initial character set for servers >= 4.1.0.
       (Bug#3146: http://bugs.mysql.com/3146)

     * Support placeholder for parameter metadata for server >=
       4.1.2. (Bug#3146: http://bugs.mysql.com/3146)

     * Added gatherPerformanceMetrics property, along with properties
       to control when/where this info gets logged (see docs for more
       info).

     * Fixed case when no parameters could cause a
       NullPointerException in
       CallableStatement.setOutputParameters().

     * Enabled callable statement caching via cacheCallableStmts
       property.

     * Fixed sending of split packets for large queries, enabled nio
       ability to send large packets as well.

     * Added .toString() functionality to ServerPreparedStatement,
       which should help if you're trying to debug a query that is a
       prepared statement (it shows SQL as the server would process).

     * Added logSlowQueries property, along with
       slowQueriesThresholdMillis property to control when a query
       should be considered "slow."

     * Removed wrapping of exceptions in MysqlIO.changeUser().

     * Fixed stored procedure parameter parsing info when size was
       specified for a parameter (for example, char(), varchar()).

     * ServerPreparedStatements weren't actually de-allocating
       server-side resources when .close() was called.

     * Fixed case when no output parameters specified for a stored
       procedure caused a bogus query to be issued to retrieve out
       parameters, leading to a syntax error from the server.

A.3.15. Changes in MySQL Connector/J 3.1.1 (14 February 2004 alpha)

   Bugs fixed:

     * Use DocBook version of docs for shipped versions of drivers.
       (Bug#2671: http://bugs.mysql.com/2671)

     * NULL fields were not being encoded correctly in all cases in
       server-side prepared statements.
       (Bug#2671: http://bugs.mysql.com/2671)

     * Fixed rare buffer underflow when writing numbers into buffers
       for sending prepared statement execution requests.
       (Bug#2671: http://bugs.mysql.com/2671)

     * Fixed ConnectionProperties that weren't properly exposed via
       accessors, cleaned up ConnectionProperties code.
       (Bug#2623: http://bugs.mysql.com/2623)

     * Class-cast exception when using scrolling result sets and
       server-side prepared statements.
       (Bug#2623: http://bugs.mysql.com/2623)

     * Merged unbuffered input code from 3.0.
       (Bug#2623: http://bugs.mysql.com/2623)

     * Enabled streaming of result sets from server-side prepared
       statements. (Bug#2606: http://bugs.mysql.com/2606)

     * Server-side prepared statements were not returning datatype
       YEAR (http://dev.mysql.com/doc/refman/5.0/en/year.html)
       correctly. (Bug#2606: http://bugs.mysql.com/2606)

     * Fixed charset conversion issue in getTables().
       (Bug#2502: http://bugs.mysql.com/2502)

     * Implemented multiple result sets returned from a statement or
       stored procedure. (Bug#2502: http://bugs.mysql.com/2502)

     * Implemented Connection.prepareCall(), and DatabaseMetaData.
       getProcedures() and getProcedureColumns().
       (Bug#2359: http://bugs.mysql.com/2359)

     * Merged prepared statement caching, and .getMetaData() support
       from 3.0 branch. (Bug#2359: http://bugs.mysql.com/2359)

     * Fixed off-by-1900 error in some cases for years in
       TimeUtil.fastDate/TimeCreate() when unpacking results from
       server-side prepared statements.
       (Bug#2359: http://bugs.mysql.com/2359)

     * Reset long binary parameters in ServerPreparedStatement when
       clearParameters() is called, by sending COM_RESET_STMT to the
       server. (Bug#2359: http://bugs.mysql.com/2359)

     * NULL values for numeric types in binary encoded result sets
       causing NullPointerExceptions.
       (Bug#2359: http://bugs.mysql.com/2359)

     * Display where/why a connection was implicitly closed (to aid
       debugging). (Bug#1673: http://bugs.mysql.com/1673)

     * DatabaseMetaData.getColumns() is not returning correct column
       ordinal info for non-'%' column name patterns.
       (Bug#1673: http://bugs.mysql.com/1673)

     * Fixed NullPointerException in
       ServerPreparedStatement.setTimestamp(), as well as year and
       month descrepencies in ServerPreparedStatement.setTimestamp(),
       setDate(). (Bug#1673: http://bugs.mysql.com/1673)

     * Added ability to have multiple database/JVM targets for
       compliance and regression/unit tests in build.xml.
       (Bug#1673: http://bugs.mysql.com/1673)

     * Fixed sending of queries larger than 16M.
       (Bug#1673: http://bugs.mysql.com/1673)

     * Merged fix of datatype mapping from MySQL type FLOAT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html) to
       java.sql.Types.REAL from 3.0 branch.
       (Bug#1673: http://bugs.mysql.com/1673)

     * Fixed NPE and year/month bad conversions when accessing some
       datetime functionality in ServerPreparedStatements and their
       resultant result sets. (Bug#1673: http://bugs.mysql.com/1673)

     * Added named and indexed input/output parameter support to
       CallableStatement. MySQL-5.0.x or newer.
       (Bug#1673: http://bugs.mysql.com/1673)

     * CommunicationsException implemented, that tries to determine
       why communications was lost with a server, and displays
       possible reasons when .getMessage() is called.
       (Bug#1673: http://bugs.mysql.com/1673)

     * Detect collation of column for RSMD.isCaseSensitive().
       (Bug#1673: http://bugs.mysql.com/1673)

     * Optimized Buffer.readLenByteArray() to return shared empty
       byte array when length is 0.

     * Fix support for table aliases when checking for all primary
       keys in UpdatableResultSet.

     * Unpack "unknown" data types from server prepared statements as
       Strings.

     * Implemented Statement.getWarnings() for MySQL-4.1 and newer
       (using SHOW WARNINGS
       (http://dev.mysql.com/doc/refman/5.0/en/show-warnings.html)).

     * Ensure that warnings are cleared before executing queries on
       prepared statements, as-per JDBC spec (now that we support
       warnings).

     * Correctly initialize datasource properties from JNDI Refs,
       including explicitly specified URLs.

     * Implemented long data (Blobs, Clobs, InputStreams, Readers)
       for server prepared statements.

     * Deal with 0-length tokens in EscapeProcessor (caused by
       callable statement escape syntax).

     * DatabaseMetaData now reports supportsStoredProcedures() for
       MySQL versions >= 5.0.0

     * Support for mysql_change_user()
       (http://dev.mysql.com/doc/refman/5.0/en/mysql-change-user.html
       ). See the changeUser() method in com.mysql.jdbc.Connection.

     * Removed useFastDates connection property.

     * Support for NIO. Use useNIO=true on platforms that support
       NIO.

     * Check for closed connection on delete/update/insert row
       operations in UpdatableResultSet.

     * Support for transaction savepoints (MySQL >= 4.0.14 or 4.1.1).

     * Support "old" profileSql capitalization in
       ConnectionProperties. This property is deprecated, you should
       use profileSQL if possible.

     * Fixed character encoding issues when converting bytes to ASCII
       when MySQL doesn't provide the character set, and the JVM is
       set to a multi-byte encoding (usually affecting retrieval of
       numeric values).

     * Centralized setting of result set type and concurrency.

     * Fixed bug with UpdatableResultSets not using client-side
       prepared statements.

     * Default result set type changed to TYPE_FORWARD_ONLY (JDBC
       compliance).

     * Fixed IllegalAccessError to Calendar.getTimeInMillis() in
       DateTimeValue (for JDK < 1.4).

     * Allow contents of PreparedStatement.setBlob() to be retained
       between calls to .execute*().

     * Fixed stack overflow in Connection.prepareCall() (bad merge).

     * Refactored how connection properties are set and exposed as
       DriverPropertyInfo as well as Connection and DataSource
       properties.

     * Reduced number of methods called in average query to be more
       efficient.

     * Prepared Statements will be re-prepared on auto-reconnect. Any
       errors encountered are postponed until first attempt to
       re-execute the re-prepared statement.

A.3.16. Changes in MySQL Connector/J 3.1.0 (18 February 2003 alpha)

   Bugs fixed:

     * Added useServerPrepStmts property (default false). The driver
       will use server-side prepared statements when the server
       version supports them (4.1 and newer) when this property is
       set to true. It is currently set to false by default until all
       bind/fetch functionality has been implemented. Currently only
       DML prepared statements are implemented for 4.1 server-side
       prepared statements.

     * Added requireSSL property.

     * Track open Statements, close all when Connection.close() is
       called (JDBC compliance).

A.4. Changes in MySQL Connector/J 3.0.x

A.4.1. Changes in MySQL Connector/J 3.0.17 (23 June 2005)

   Bugs fixed:

     * Workaround for server Bug#9098: http://bugs.mysql.com/9098:
       Default values of CURRENT_* for DATE
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html), TIME
       (http://dev.mysql.com/doc/refman/5.0/en/time.html), DATETIME
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html), and
       TIMESTAMP
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html) columns
       can't be distinguished from string values, so
       UpdatableResultSet.moveToInsertRow() generates bad SQL for
       inserting default values.
       (Bug#8812: http://bugs.mysql.com/8812)

     * NON_UNIQUE column from DBMD.getIndexInfo() returned inverted
       value. (Bug#8812: http://bugs.mysql.com/8812)

     * EUCKR charset is sent as SET NAMES euc_kr which MySQL-4.1 and
       newer doesn't understand.
       (Bug#8629: http://bugs.mysql.com/8629)

     * Added support for the EUC_JP_Solaris character encoding, which
       maps to a MySQL encoding of eucjpms (backported from 3.1
       branch). This only works on servers that support eucjpms,
       namely 5.0.3 or later. (Bug#8629: http://bugs.mysql.com/8629)

     * Use hex escapes for PreparedStatement.setBytes() for
       double-byte charsets including "aliases" Windows-31J, CP934,
       MS932. (Bug#8629: http://bugs.mysql.com/8629)

     * DatabaseMetaData.supportsSelectForUpdate() returns correct
       value based on server version.
       (Bug#8629: http://bugs.mysql.com/8629)

     * Which requires hex escaping of binary data when using
       multi-byte charsets with prepared statements.
       (Bug#8064: http://bugs.mysql.com/8064)

     * Fixed duplicated code in configureClientCharset() that
       prevented useOldUTF8Behavior=true from working properly.
       (Bug#7952: http://bugs.mysql.com/7952)

     * Backported SQLState codes mapping from Connector/J 3.1, enable
       with useSqlStateCodes=true as a connection property, it
       defaults to false in this release, so that we don't break
       legacy applications (it defaults to true starting with
       Connector/J 3.1). (Bug#7686: http://bugs.mysql.com/7686)

     * Timestamp key column data needed _binary stripped for
       UpdatableResultSet.refreshRow().
       (Bug#7686: http://bugs.mysql.com/7686)

     * MS932, SHIFT_JIS, and Windows_31J not recognized as aliases
       for sjis. (Bug#7607: http://bugs.mysql.com/7607)

     * Handle streaming result sets with more than 2 billion rows
       properly by fixing wraparound of row number counter.
       (Bug#7601: http://bugs.mysql.com/7601)

     * PreparedStatement.fixDecimalExponent() adding extra +, making
       number unparseable by MySQL server.
       (Bug#7601: http://bugs.mysql.com/7601)

     * Escape sequence {fn convert(..., type)} now supports
       ODBC-style types that are prepended by SQL_.
       (Bug#7601: http://bugs.mysql.com/7601)

     * Statements created from a pooled connection were returning
       physical connection instead of logical connection when
       getConnection() was called.
       (Bug#7316: http://bugs.mysql.com/7316)

     * Support new protocol type MYSQL_TYPE_VARCHAR.
       (Bug#7081: http://bugs.mysql.com/7081)

     * Added useOldUTF8Behavior' configuration property, which causes
       JDBC driver to act like it did with MySQL-4.0.x and earlier
       when the character encoding is utf-8 when connected to
       MySQL-4.1 or newer. (Bug#7081: http://bugs.mysql.com/7081)

     * DatabaseMetaData.getIndexInfo() ignored unique parameter.
       (Bug#7081: http://bugs.mysql.com/7081)

     * PreparedStatement.fixDecimalExponent() adding extra +, making
       number unparseable by MySQL server.
       (Bug#7061: http://bugs.mysql.com/7061)

     * PreparedStatements don't encode Big5 (and other multi-byte)
       character sets correctly in static SQL strings.
       (Bug#7033: http://bugs.mysql.com/7033)

     * Connections starting up failed-over (due to down master) never
       retry master. (Bug#6966: http://bugs.mysql.com/6966)

     * Adding CP943 to aliases for sjis.
       (Bug#6549: http://bugs.mysql.com/6549,
       Bug#7607: http://bugs.mysql.com/7607)

     * Timestamp/Time conversion goes in the wrong "direction" when
       useTimeZone=true and server time zone differs from client time
       zone. (Bug#5874: http://bugs.mysql.com/5874)

A.4.2. Changes in MySQL Connector/J 3.0.16 (15 November 2004)

   Bugs fixed:

     * Made TINYINT(1) -> BIT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)/Bo
       olean conversion configurable via tinyInt1isBit property
       (default true to be JDBC compliant out of the box).
       (Bug#5664: http://bugs.mysql.com/5664)

     * Off-by-one bug in Buffer.readString(string).
       (Bug#5664: http://bugs.mysql.com/5664)

     * ResultSet.updateByte() when on insert row throws
       ArrayOutOfBoundsException.
       (Bug#5664: http://bugs.mysql.com/5664)

     * Fixed regression where useUnbufferedInput was defaulting to
       false. (Bug#5664: http://bugs.mysql.com/5664)

     * ResultSet.getTimestamp() on a column with TIME
       (http://dev.mysql.com/doc/refman/5.0/en/time.html) in it
       fails. (Bug#5664: http://bugs.mysql.com/5664)

     * Fixed DatabaseMetaData.getTypes() returning incorrect (this
       is, nonnegative) scale for the NUMERIC
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       type. (Bug#5664: http://bugs.mysql.com/5664)

     * Only set character_set_results
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_character_set_results) during connection
       establishment if server version >= 4.1.1.
       (Bug#5664: http://bugs.mysql.com/5664)

     * Fixed ResultSetMetaData.isReadOnly() to detect nonwritable
       columns when connected to MySQL-4.1 or newer, based on
       existence of "original" table and column names.

     * Re-issue character set configuration commands when re-using
       pooled connections and/or Connection.changeUser() when
       connected to MySQL-4.1 or newer.

A.4.3. Changes in MySQL Connector/J 3.0.15 (04 September 2004)

   Bugs fixed:

     * ResultSet.getMetaData() should not return incorrectly
       initialized metadata if the result set has been closed, but
       should instead throw an SQLException. Also fixed for getRow()
       and getWarnings() and traversal methods by calling
       checkClosed() before operating on instance-level fields that
       are nullified during .close().
       (Bug#5069: http://bugs.mysql.com/5069)

     * Use _binary introducer for PreparedStatement.setBytes() and
       set*Stream() when connected to MySQL-4.1.x or newer to avoid
       misinterpretation during character conversion.
       (Bug#5069: http://bugs.mysql.com/5069)

     * Parse new time zone variables from 4.1.x servers.
       (Bug#5069: http://bugs.mysql.com/5069)

     * ResultSet should release Field[] instance in .close().
       (Bug#5022: http://bugs.mysql.com/5022)

     * RSMD.getPrecision() returning 0 for nonnumeric types (should
       return max length in chars for nonbinary types, max length in
       bytes for binary types). This fix also fixes mapping of
       RSMD.getColumnType() and RSMD.getColumnTypeName() for the BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) types based
       on the length sent from the server (the server doesn't
       distinguish between TINYBLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html), BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html), MEDIUMBLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) or LONGBLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) at the
       network protocol level).
       (Bug#4880: http://bugs.mysql.com/4880)

     * "Production" is now "GA" (General Availability) in naming
       scheme of distributions.
       (Bug#4860: http://bugs.mysql.com/4860,
       Bug#4138: http://bugs.mysql.com/4138)

     * DBMD.getColumns() returns incorrect JDBC type for unsigned
       columns. This affects type mappings for all numeric types in
       the RSMD.getColumnType() and RSMD.getColumnTypeNames() methods
       as well, to ensure that "like" types from DBMD.getColumns()
       match up with what RSMD.getColumnType() and
       getColumnTypeNames() return.
       (Bug#4860: http://bugs.mysql.com/4860,
       Bug#4138: http://bugs.mysql.com/4138)

     * Calling .close() twice on a PooledConnection causes NPE.
       (Bug#4808: http://bugs.mysql.com/4808)

     * DOUBLE
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       mapped twice in DBMD.getTypeInfo().
       (Bug#4742: http://bugs.mysql.com/4742)

     * Added FLOSS license exemption.
       (Bug#4742: http://bugs.mysql.com/4742)

     * Removed redundant calls to checkRowPos() in ResultSet.
       (Bug#4334: http://bugs.mysql.com/4334)

     * Failover for autoReconnect not using port numbers for any
       hosts, and not retrying all hosts.

Warning
       This required a change to the SocketFactory connect() method
       signature, which is now public Socket connect(String host, int
       portNumber, Properties props); therefore, any third-party
       socket factories will have to be changed to support this
       signature.
       (Bug#4334: http://bugs.mysql.com/4334)

     * Logical connections created by MysqlConnectionPoolDataSource
       will now issue a rollback() when they are closed and sent back
       to the pool. If your application server/connection pool
       already does this for you, you can set the
       rollbackOnPooledClose property to false to avoid the overhead
       of an extra rollback(). (Bug#4334: http://bugs.mysql.com/4334)

     * StringUtils.escapeEasternUnicodeByteStream was still broken
       for GBK. (Bug#4010: http://bugs.mysql.com/4010)

A.4.4. Changes in MySQL Connector/J 3.0.14 (28 May 2004)

   Bugs fixed:

     * Fixed URL parsing error.

A.4.5. Changes in MySQL Connector/J 3.0.13 (27 May 2004)

   Bugs fixed:

     * No Database Selected when using MysqlConnectionPoolDataSource.
       (Bug#3920: http://bugs.mysql.com/3920)

     * PreparedStatement.getGeneratedKeys() method returns only 1
       result for batched insertions.
       (Bug#3873: http://bugs.mysql.com/3873)

     * Using a MySQLDatasource without server name fails.
       (Bug#3848: http://bugs.mysql.com/3848)

A.4.6. Changes in MySQL Connector/J 3.0.12 (18 May 2004)

   Bugs fixed:

     * Inconsistent reporting of data type. The server still doesn't
       return all types for *BLOBs *TEXT correctly, so the driver
       won't return those correctly.
       (Bug#3570: http://bugs.mysql.com/3570)

     * UpdatableResultSet not picking up default values for
       moveToInsertRow(). (Bug#3557: http://bugs.mysql.com/3557)

     * Not specifying database in URL caused MalformedURL exception.
       (Bug#3554: http://bugs.mysql.com/3554)

     * Auto-convert MySQL encoding names to Java encoding names if
       used for characterEncoding property.
       (Bug#3554: http://bugs.mysql.com/3554)

     * Use junit.textui.TestRunner for all unit tests (to allow them
       to be run from the command line outside of Ant or Eclipse).
       (Bug#3554: http://bugs.mysql.com/3554)

     * Added encoding names that are recognized on some JVMs to fix
       case where they were reverse-mapped to MySQL encoding names
       incorrectly. (Bug#3554: http://bugs.mysql.com/3554)

     * Made StringRegressionTest 4.1-unicode aware.
       (Bug#3520: http://bugs.mysql.com/3520)

     * Fixed regression in PreparedStatement.setString() and eastern
       character encodings. (Bug#3520: http://bugs.mysql.com/3520)

     * DBMD.getSQLStateType() returns incorrect value.
       (Bug#3520: http://bugs.mysql.com/3520)

     * Renamed StringUtils.escapeSJISByteStream() to more appropriate
       escapeEasternUnicodeByteStream().
       (Bug#3511: http://bugs.mysql.com/3511)

     * StringUtils.escapeSJISByteStream() not covering all eastern
       double-byte charsets correctly.
       (Bug#3511: http://bugs.mysql.com/3511)

     * Return creating statement for ResultSets created by
       getGeneratedKeys(). (Bug#2957: http://bugs.mysql.com/2957)

     * Use SET character_set_results during initialization to allow
       any charset to be returned to the driver for result sets.
       (Bug#2670: http://bugs.mysql.com/2670)

     * Don't truncate BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) or CLOB
       values when using setBytes() and/or
       setBinary/CharacterStream(). .
       (Bug#2670: http://bugs.mysql.com/2670)

     * Dynamically configure character set mappings for field-level
       character sets on MySQL-4.1.0 and newer using SHOW COLLATION
       (http://dev.mysql.com/doc/refman/5.0/en/show-collation.html)
       when connecting. (Bug#2670: http://bugs.mysql.com/2670)

     * Map binary character set to US-ASCII to support DATETIME
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html) charset
       recognition for servers >= 4.1.2.
       (Bug#2670: http://bugs.mysql.com/2670)

     * Use charsetnr returned during connect to encode queries before
       issuing SET NAMES on MySQL >= 4.1.0.
       (Bug#2670: http://bugs.mysql.com/2670)

     * Add helper methods to ResultSetMetaData
       (getColumnCharacterEncoding() and getColumnCharacterSet()) to
       allow end-users to see what charset the driver thinks it
       should be using for the column.
       (Bug#2670: http://bugs.mysql.com/2670)

     * Only set character_set_results
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_character_set_results) for MySQL >= 4.1.0.
       (Bug#2670: http://bugs.mysql.com/2670)

     * Allow url parameter for MysqlDataSource and
       MysqlConnectionPool DataSource so that passing of other
       properties is possible from inside appservers.

     * Don't escape SJIS/GBK/BIG5 when using MySQL-4.1 or newer.

     * Backport documentation tooling from 3.1 branch.

     * Added failOverReadOnly property, to allow end-user to
       configure state of connection (read-only/writable) when failed
       over.

     * Allow java.util.Date to be sent in as parameter to
       PreparedStatement.setObject(), converting it to a Timestamp to
       maintain full precision. .
       (Bug#103: http://bugs.mysql.com/103)

     * Add unsigned attribute to DatabaseMetaData.getColumns() output
       in the TYPE_NAME column.

     * Map duplicate key and foreign key errors to SQLState of 23000.

     * Backported "change user" and "reset server state"
       functionality from 3.1 branch, to allow clients of
       MysqlConnectionPoolDataSource to reset server state on
       getConnection() on a pooled connection.

A.4.7. Changes in MySQL Connector/J 3.0.11 (19 February 2004)

   Bugs fixed:

     * Return java.lang.Double for FLOAT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       type from ResultSetMetaData.getColumnClassName().
       (Bug#2855: http://bugs.mysql.com/2855)

     * Return [B instead of java.lang.Object for BINARY
       (http://dev.mysql.com/doc/refman/5.0/en/binary-varbinary.html)
       , VARBINARY
       (http://dev.mysql.com/doc/refman/5.0/en/binary-varbinary.html)
       and LONGVARBINARY types from
       ResultSetMetaData.getColumnClassName() (JDBC compliance).
       (Bug#2855: http://bugs.mysql.com/2855)

     * Issue connection events on all instances created from a
       ConnectionPoolDataSource.
       (Bug#2855: http://bugs.mysql.com/2855)

     * Return java.lang.Integer for TINYINT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       and SMALLINT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       types from ResultSetMetaData.getColumnClassName().
       (Bug#2852: http://bugs.mysql.com/2852)

     * Added useUnbufferedInput parameter, and now use it by default
       (due to JVM issue
       http://developer.java.sun.com/developer/bugParade/bugs/4401235
       .html) (Bug#2578: http://bugs.mysql.com/2578)

     * Fixed failover always going to last host in list.
       (Bug#2578: http://bugs.mysql.com/2578)

     * Detect on/off or 1, 2, 3 form of lower_case_table_names
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_lower_case_table_names) value on server.
       (Bug#2578: http://bugs.mysql.com/2578)

     * AutoReconnect time was growing faster than exponentially.
       (Bug#2447: http://bugs.mysql.com/2447)

     * Trigger a SET NAMES utf8 when encoding is forced to utf8 or
       utf-8 via the characterEncoding property. Previously, only the
       Java-style encoding name of utf-8 would trigger this.

A.4.8. Changes in MySQL Connector/J 3.0.10 (13 January 2004)

   Bugs fixed:

     * Enable caching of the parsing stage of prepared statements via
       the cachePrepStmts, prepStmtCacheSize, and
       prepStmtCacheSqlLimit properties (disabled by default).
       (Bug#2006: http://bugs.mysql.com/2006)

     * Fixed security exception when used in Applets (applets can't
       read the system property file.encoding which is needed for
       LOAD DATA LOCAL INFILE
       (http://dev.mysql.com/doc/refman/5.0/en/load-data.html)).
       (Bug#2006: http://bugs.mysql.com/2006)

     * Speed up parsing of PreparedStatements, try to use one-pass
       whenever possible. (Bug#2006: http://bugs.mysql.com/2006)

     * Fixed exception Unknown character set 'danish' on connect with
       JDK-1.4.0 (Bug#2006: http://bugs.mysql.com/2006)

     * Fixed mappings in SQLError to report deadlocks with SQLStates
       of 41000. (Bug#2006: http://bugs.mysql.com/2006)

     * Removed static synchronization bottleneck from instance
       factory method of SingleByteCharsetConverter.
       (Bug#2006: http://bugs.mysql.com/2006)

     * Removed static synchronization bottleneck from
       PreparedStatement.setTimestamp().
       (Bug#2006: http://bugs.mysql.com/2006)

     * ResultSet.findColumn() should use first matching column name
       when there are duplicate column names in SELECT
       (http://dev.mysql.com/doc/refman/5.0/en/select.html) query
       (JDBC-compliance). (Bug#2006: http://bugs.mysql.com/2006)

     * maxRows property would affect internal statements, so check it
       for all statement creation internal to the driver, and set to
       0 when it is not. (Bug#2006: http://bugs.mysql.com/2006)

     * Use constants for SQLStates.
       (Bug#2006: http://bugs.mysql.com/2006)

     * Map charset ko18_ru to ko18r when connected to MySQL-4.1.0 or
       newer. (Bug#2006: http://bugs.mysql.com/2006)

     * Ensure that Buffer.writeString() saves room for the \0.
       (Bug#2006: http://bugs.mysql.com/2006)

     * ArrayIndexOutOfBounds when parameter number == number of
       parameters + 1. (Bug#1958: http://bugs.mysql.com/1958)

     * Connection property maxRows not honored.
       (Bug#1933: http://bugs.mysql.com/1933)

     * Statements being created too many times in
       DBMD.extractForeignKeyFromCreateTable().
       (Bug#1925: http://bugs.mysql.com/1925)

     * Support escape sequence {fn convert ... }.
       (Bug#1914: http://bugs.mysql.com/1914)

     * Implement ResultSet.updateClob().
       (Bug#1913: http://bugs.mysql.com/1913)

     * Autoreconnect code didn't set catalog upon reconnect if it had
       been changed. (Bug#1913: http://bugs.mysql.com/1913)

     * ResultSet.getObject() on TINYINT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       and SMALLINT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       columns should return Java type Integer.
       (Bug#1913: http://bugs.mysql.com/1913)

     * Added more descriptive error message Server Configuration
       Denies Access to DataSource, as well as retrieval of message
       from server. (Bug#1913: http://bugs.mysql.com/1913)

     * ResultSetMetaData.isCaseSensitive() returned wrong value for
       CHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html)/VARCHAR
       (http://dev.mysql.com/doc/refman/5.0/en/char.html) columns.
       (Bug#1913: http://bugs.mysql.com/1913)

     * Added alwaysClearStream connection property, which causes the
       driver to always empty any remaining data on the input stream
       before each query. (Bug#1913: http://bugs.mysql.com/1913)

     * DatabaseMetaData.getSystemFunction() returning bad function
       VResultsSion. (Bug#1775: http://bugs.mysql.com/1775)

     * Foreign Keys column sequence is not consistent in
       DatabaseMetaData.getImported/Exported/CrossReference().
       (Bug#1731: http://bugs.mysql.com/1731)

     * Fix for ArrayIndexOutOfBounds exception when using
       Statement.setMaxRows(). (Bug#1695: http://bugs.mysql.com/1695)

     * Subsequent call to ResultSet.updateFoo() causes NPE if result
       set is not updatable. (Bug#1630: http://bugs.mysql.com/1630)

     * Fix for 4.1.1-style authentication with no password.
       (Bug#1630: http://bugs.mysql.com/1630)

     * Cross-database updatable result sets are not checked for
       updatability correctly. (Bug#1592: http://bugs.mysql.com/1592)

     * DatabaseMetaData.getColumns() should return Types.LONGVARCHAR
       for MySQL LONGTEXT
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) type.
       (Bug#1592: http://bugs.mysql.com/1592)

     * Fixed regression of Statement.getGeneratedKeys() and REPLACE
       (http://dev.mysql.com/doc/refman/5.0/en/replace.html)
       statements. (Bug#1576: http://bugs.mysql.com/1576)

     * Barge blobs and split packets not being read correctly.
       (Bug#1576: http://bugs.mysql.com/1576)

     * Backported fix for aliased tables and UpdatableResultSets in
       checkUpdatability() method from 3.1 branch.
       (Bug#1534: http://bugs.mysql.com/1534)

     * "Friendlier" exception message for PacketTooLargeException.
       (Bug#1534: http://bugs.mysql.com/1534)

     * Don't count quoted IDs when inside a 'string' in
       PreparedStatement parsing.
       (Bug#1511: http://bugs.mysql.com/1511)

A.4.9. Changes in MySQL Connector/J 3.0.9 (07 October 2003)

   Bugs fixed:

     * ResultSet.get/setString mashing char 127.
       (Bug#1247: http://bugs.mysql.com/1247)

     * Added property to "clobber" streaming results, by setting the
       clobberStreamingResults property to true (the default is
       false). This will cause a "streaming" ResultSet to be
       automatically closed, and any oustanding data still streaming
       from the server to be discarded if another query is executed
       before all the data has been read from the server.
       (Bug#1247: http://bugs.mysql.com/1247)

     * Added com.mysql.jdbc.util.BaseBugReport to help creation of
       testcases for bug reports.
       (Bug#1247: http://bugs.mysql.com/1247)

     * Backported authentication changes for 4.1.1 and newer from 3.1
       branch. (Bug#1247: http://bugs.mysql.com/1247)

     * Made databaseName, portNumber, and serverName optional
       parameters for MysqlDataSourceFactory.
       (Bug#1246: http://bugs.mysql.com/1246)

     * Optimized CLOB.setChracterStream().
       (Bug#1131: http://bugs.mysql.com/1131)

     * Fixed CLOB.truncate(). (Bug#1130: http://bugs.mysql.com/1130)

     * Fixed deadlock issue with Statement.setMaxRows().
       (Bug#1099: http://bugs.mysql.com/1099)

     * DatabaseMetaData.getColumns() getting confused about the
       keyword "set" in character columns.
       (Bug#1099: http://bugs.mysql.com/1099)

     * Clip +/- INF (to smallest and largest representative values
       for the type in MySQL) and NaN (to 0) for
       setDouble/setFloat(), and issue a warning on the statement
       when the server does not support +/- INF or NaN.
       (Bug#884: http://bugs.mysql.com/884)

     * Don't fire connection closed events when closing pooled
       connections, or on PooledConnection.getConnection() with
       already open connections. (Bug#884: http://bugs.mysql.com/884)

     * Double-escaping of '\' when charset is SJIS or GBK and '\'
       appears in nonescaped input.
       (Bug#879: http://bugs.mysql.com/879)

     * When emptying input stream of unused rows for "streaming"
       result sets, have the current thread yield() every 100 rows in
       order to not monopolize CPU time.
       (Bug#879: http://bugs.mysql.com/879)

     * Issue exception on ResultSet.getXXX() on empty result set
       (wasn't caught in some cases).
       (Bug#848: http://bugs.mysql.com/848)

     * Don't hide messages from exceptions thrown in I/O layers.
       (Bug#848: http://bugs.mysql.com/848)

     * Fixed regression in large split-packet handling.
       (Bug#848: http://bugs.mysql.com/848)

     * Better diagnostic error messages in exceptions for "streaming"
       result sets. (Bug#848: http://bugs.mysql.com/848)

     * Don't change timestamp TZ twice if useTimezone==true.
       (Bug#774: http://bugs.mysql.com/774)

     * Don't wrap SQLExceptions in RowDataDynamic.
       (Bug#688: http://bugs.mysql.com/688)

     * Don't try and reset isolation level on reconnect if MySQL
       doesn't support them. (Bug#688: http://bugs.mysql.com/688)

     * The insertRow in an UpdatableResultSet is now loaded with the
       default column values when moveToInsertRow() is called.
       (Bug#688: http://bugs.mysql.com/688)

     * DatabaseMetaData.getColumns() wasn't returning NULL for
       default values that are specified as NULL.
       (Bug#688: http://bugs.mysql.com/688)

     * Change default statement type/concurrency to TYPE_FORWARD_ONLY
       and CONCUR_READ_ONLY (spec compliance).
       (Bug#688: http://bugs.mysql.com/688)

     * Fix UpdatableResultSet to return values for getXXX() when on
       insert row. (Bug#675: http://bugs.mysql.com/675)

     * Support InnoDB contraint names when extracting foreign key
       information in DatabaseMetaData (implementing ideas from
       Parwinder Sekhon). (Bug#664: http://bugs.mysql.com/664,
       Bug#517: http://bugs.mysql.com/517)

     * Backported 4.1 protocol changes from 3.1 branch (server-side
       SQL states, new field information, larger client capability
       flags, connect-with-database, and so forth).
       (Bug#664: http://bugs.mysql.com/664,
       Bug#517: http://bugs.mysql.com/517)

     * refreshRow didn't work when primary key values contained
       values that needed to be escaped (they ended up being doubly
       escaped). (Bug#661: http://bugs.mysql.com/661)

     * Fixed ResultSet.previous() behavior to move current position
       to before result set when on first row of result set.
       (Bug#496: http://bugs.mysql.com/496)

     * Fixed Statement and PreparedStatement issuing bogus queries
       when setMaxRows() had been used and a LIMIT clause was present
       in the query. (Bug#496: http://bugs.mysql.com/496)

     * Faster date handling code in ResultSet and PreparedStatement
       (no longer uses Date methods that synchronize on static
       calendars).

     * Fixed test for end of buffer in Buffer.readString().

A.4.10. Changes in MySQL Connector/J 3.0.8 (23 May 2003)

   Bugs fixed:

     * Fixed SJIS encoding bug, thanks to Naoto Sato.
       (Bug#378: http://bugs.mysql.com/378)

     * Fix problem detecting server character set in some cases.
       (Bug#378: http://bugs.mysql.com/378)

     * Allow multiple calls to Statement.close().
       (Bug#378: http://bugs.mysql.com/378)

     * Return correct number of generated keys when using REPLACE
       (http://dev.mysql.com/doc/refman/5.0/en/replace.html)
       statements. (Bug#378: http://bugs.mysql.com/378)

     * Unicode character 0xFFFF in a string would cause the driver to
       throw an ArrayOutOfBoundsException. .
       (Bug#378: http://bugs.mysql.com/378)

     * Fix row data decoding error when using very large packets.
       (Bug#378: http://bugs.mysql.com/378)

     * Optimized row data decoding.
       (Bug#378: http://bugs.mysql.com/378)

     * Issue exception when operating on an already closed prepared
       statement. (Bug#378: http://bugs.mysql.com/378)

     * Optimized usage of EscapeProcessor.
       (Bug#378: http://bugs.mysql.com/378)

     * Use JVM charset with file names and LOAD DATA [LOCAL] INFILE.

     * Fix infinite loop with Connection.cleanup().

     * Changed Ant target compile-core to compile-driver, and made
       testsuite compilation a separate target.

     * Fixed result set not getting set for
       Statement.executeUpdate(), which affected getGeneratedKeys()
       and getUpdateCount() in some cases.

     * Return list of generated keys when using multi-value INSERTS
       with Statement.getGeneratedKeys().

     * Allow bogus URLs in Driver.getPropertyInfo().

A.4.11. Changes in MySQL Connector/J 3.0.7 (08 April 2003)

   Bugs fixed:

     * Fixed charset issues with database metadata (charset was not
       getting set correctly).

     * You can now toggle profiling on/off using
       Connection.setProfileSql(boolean).

     * 4.1 Column Metadata fixes.

     * Fixed MysqlPooledConnection.close() calling wrong event type.

     * Fixed StringIndexOutOfBoundsException in
       PreparedStatement.setClob().

     * IOExceptions during a transaction now cause the Connection to
       be closed.

     * Remove synchronization from Driver.connect() and
       Driver.acceptsUrl().

     * Fixed missing conversion for YEAR
       (http://dev.mysql.com/doc/refman/5.0/en/year.html) type in
       ResultSetMetaData.getColumnTypeName().

     * Updatable ResultSets can now be created for aliased
       tables/columns when connected to MySQL-4.1 or newer.

     * Fixed LOAD DATA LOCAL INFILE
       (http://dev.mysql.com/doc/refman/5.0/en/load-data.html) bug
       when file > max_allowed_packet
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_max_allowed_packet).

     * Don't pick up indexes that start with pri as primary keys for
       DBMD.getPrimaryKeys().

     * Ensure that packet size from alignPacketSize() does not exceed
       max_allowed_packet
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_max_allowed_packet) (JVM bug)

     * Don't reset Connection.isReadOnly() when autoReconnecting.

     * Fixed escaping of 0x5c ('\') character for GBK and Big5
       charsets.

     * Fixed ResultSet.getTimestamp() when underlying field is of
       type DATE
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html).

     * Throw SQLExceptions when trying to do operations on a
       forcefully closed Connection (that is, when a communication
       link failure occurs).

A.4.12. Changes in MySQL Connector/J 3.0.6 (18 February 2003)

   Bugs fixed:

     * Backported 4.1 charset field info changes from Connector/J
       3.1.

     * Fixed Statement.setMaxRows() to stop sending LIMIT type
       queries when not needed (performance).

     * Fixed DBMD.getTypeInfo() and DBMD.getColumns() returning
       different value for precision in TEXT
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) and BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) types.

     * Fixed SQLExceptions getting swallowed on initial connect.

     * Fixed ResultSetMetaData to return "" when catalog not known.
       Fixes NullPointerExceptions with Sun's CachedRowSet.

     * Allow ignoring of warning for "non transactional tables"
       during rollback (compliance/usability) by setting
       ignoreNonTxTables property to true.

     * Clean up Statement query/method mismatch tests (that is,
       INSERT (http://dev.mysql.com/doc/refman/5.0/en/insert.html)
       not allowed with .executeQuery()).

     * Fixed ResultSetMetaData.isWritable() to return correct value.

     * More checks added in ResultSet traversal method to catch when
       in closed state.

     * Implemented Blob.setBytes(). You still need to pass the
       resultant Blob back into an updatable ResultSet or
       PreparedStatement to persist the changes, because MySQL does
       not support "locators".

     * Add "window" of different NULL sorting behavior to
       DBMD.nullsAreSortedAtStart (4.0.2 to 4.0.10, true; otherwise,
       no).

A.4.13. Changes in MySQL Connector/J 3.0.5 (22 January 2003)

   Bugs fixed:

     * Fixed ResultSet.isBeforeFirst() for empty result sets.

     * Added missing LONGTEXT
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) type to
       DBMD.getColumns().

     * Implemented an empty TypeMap for Connection.getTypeMap() so
       that some third-party apps work with MySQL (IBM WebSphere 5.0
       Connection pool).

     * Added update options for foreign key metadata.

     * Fixed Buffer.fastSkipLenString() causing ArrayIndexOutOfBounds
       exceptions with some queries when unpacking fields.

     * Quote table names in DatabaseMetaData.getColumns(),
       getPrimaryKeys(), getIndexInfo(), getBestRowIdentifier().

     * Retrieve TX_ISOLATION from database for
       Connection.getTransactionIsolation() when the MySQL version
       supports it, instead of an instance variable.

     * Greatly reduce memory required for setBinaryStream() in
       PreparedStatements.

A.4.14. Changes in MySQL Connector/J 3.0.4 (06 January 2003)

   Bugs fixed:

     * Streamlined character conversion and byte[] handling in
       PreparedStatements for setByte().

     * Fixed PreparedStatement.executeBatch() parameter overwriting.

     * Added quoted identifiers to database names for
       Connection.setCatalog.

     * Added support for 4.0.8-style large packets.

     * Reduce memory footprint of PreparedStatements by sharing
       outbound packet with MysqlIO.

     * Added strictUpdates property to allow control of amount of
       checking for "correctness" of updatable result sets. Set this
       to false if you want faster updatable result sets and you know
       that you create them from SELECT
       (http://dev.mysql.com/doc/refman/5.0/en/select.html)
       statements on tables with primary keys and that you have
       selected all primary keys in your query.

     * Added support for quoted identifiers in PreparedStatement
       parser.

A.4.15. Changes in MySQL Connector/J 3.0.3 (17 December 2002)

   Bugs fixed:

     * Allow user to alter behavior of Statement/
       PreparedStatement.executeBatch() via continueBatchOnError
       property (defaults to true).

     * More robust escape tokenizer: Recognize -- comments, and allow
       nested escape sequences (see testsuite.EscapeProcessingTest).

     * Fixed Buffer.isLastDataPacket() for 4.1 and newer servers.

     * NamedPipeSocketFactory now works (only intended for Windows),
       see README for instructions.

     * Changed charsToByte in SingleByteCharConverter to be
       nonstatic.

     * Use nonaliased table/column names and database names to fully
       qualify tables and columns in UpdatableResultSet (requires
       MySQL-4.1 or newer).

     * LOAD DATA LOCAL INFILE ... now works, if your server is
       configured to allow it. Can be turned off with the
       allowLoadLocalInfile property (see the README).

     * Implemented Connection.nativeSQL().

     * Fixed ResultSetMetaData.getColumnTypeName() returning BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) for TEXT
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) and TEXT
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) for BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) types.

     * Fixed charset handling in Fields.java.

     * Because of above, implemented
       ResultSetMetaData.isAutoIncrement() to use
       Field.isAutoIncrement().

     * Substitute '?' for unknown character conversions in
       single-byte character sets instead of '\0'.

     * Added CLIENT_LONG_FLAG to be able to get more column flags
       (isAutoIncrement() being the most important).

     * Honor lower_case_table_names
       (http://dev.mysql.com/doc/refman/5.0/en/server-system-variable
       s.html#sysvar_lower_case_table_names) when enabled in the
       server when doing table name comparisons in DatabaseMetaData
       methods.

     * DBMD.getImported/ExportedKeys() now handles multiple foreign
       keys per table.

     * More robust implementation of updatable result sets. Checks
       that all primary keys of the table have been selected.

     * Some MySQL-4.1 protocol support (extended field info from
       selects).

     * Check for connection closed in more Connection methods
       (createStatement, prepareStatement, setTransactionIsolation,
       setAutoCommit).

     * Fixed ResultSetMetaData.getPrecision() returning incorrect
       values for some floating-point types.

     * Changed SingleByteCharConverter to use lazy initialization of
       each converter.

A.4.16. Changes in MySQL Connector/J 3.0.2 (08 November 2002)

   Bugs fixed:

     * Implemented Clob.setString().

     * Added com.mysql.jdbc.MiniAdmin class, which allows you to send
       shutdown command to MySQL server. This is intended to be used
       when "embedding" Java and MySQL server together in an end-user
       application.

     * Added SSL support. See README for information on how to use
       it.

     * All DBMD result set columns describing schemas now return NULL
       to be more compliant with the behavior of other JDBC drivers
       for other database systems (MySQL does not support schemas).

     * Use SHOW CREATE TABLE
       (http://dev.mysql.com/doc/refman/5.0/en/show-create-table.html
       ) when possible for determining foreign key information for
       DatabaseMetaData. Also allows cascade options for DELETE
       (http://dev.mysql.com/doc/refman/5.0/en/delete.html)
       information to be returned.

     * Implemented Clob.setCharacterStream().

     * Failover and autoReconnect work only when the connection is in
       an autoCommit(false) state, in order to stay transaction-safe.

     * Fixed DBMD.supportsResultSetConcurrency() so that it returns
       true for ResultSet.TYPE_SCROLL_INSENSITIVE and
       ResultSet.CONCUR_READ_ONLY or ResultSet.CONCUR_UPDATABLE.

     * Implemented Clob.setAsciiStream().

     * Removed duplicate code from UpdatableResultSet (it can be
       inherited from ResultSet, the extra code for each method to
       handle updatability I thought might someday be necessary has
       not been needed).

     * Fixed UnsupportedEncodingException thrown when "forcing" a
       character encoding via properties.

     * Fixed incorrect conversion in ResultSet.getLong().

     * Implemented ResultSet.updateBlob().

     * Removed some not-needed temporary object creation by smarter
       use of Strings in EscapeProcessor, Connection and
       DatabaseMetaData classes.

     * Escape 0x5c character in strings for the SJIS charset.

     * PreparedStatement now honors stream lengths in
       setBinary/Ascii/Character Stream() unless you set the
       connection property useStreamLengthsInPrepStmts to false.

     * Fixed issue with updatable result sets and PreparedStatements
       not working.

     * Fixed start position off-by-1 error in Clob.getSubString().

     * Added connectTimeout parameter that allows users of JDK-1.4
       and newer to specify a maximum time to wait to establish a
       connection.

     * Fixed various non-ASCII character encoding issues.

     * Fixed ResultSet.isLast() for empty result sets (should return
       false).

     * Added driver property useHostsInPrivileges. Defaults to true.
       Affects whether or not @hostname will be used in
       DBMD.getColumn/TablePrivileges.

     * Fixed ResultSet.setFetchDirection(FETCH_UNKNOWN).

     * Added queriesBeforeRetryMaster property that specifies how
       many queries to issue when failed over before attempting to
       reconnect to the master (defaults to 50).

     * Fixed issue when calling Statement.setFetchSize() when using
       arbitrary values.

     * Properly restore connection properties when autoReconnecting
       or failing-over, including autoCommit state, and isolation
       level.

     * Implemented Clob.truncate().

A.4.17. Changes in MySQL Connector/J 3.0.1 (21 September 2002)

   Bugs fixed:

     * Charsets now automatically detected. Optimized code for
       single-byte character set conversion.

     * Fixed ResultSetMetaData.isSigned() for TINYINT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       and BIGINT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html).

     * Fixed RowDataStatic.getAt() off-by-one bug.

     * Fixed ResultSet.getRow() off-by-one bug.

     * Massive code clean-up to follow Java coding conventions (the
       time had come).

     * Implemented ResultSet.getCharacterStream().

     * Added limited Clob functionality (ResultSet.getClob(),
       PreparedStatemtent.setClob(),
       PreparedStatement.setObject(Clob).

     * Connection.isClosed() no longer "pings" the server.

     * Connection.close() issues rollback() when getAutoCommit() is
       false.

     * Added socketTimeout parameter to URL.

     * Added LOCAL TEMPORARY to table types in
       DatabaseMetaData.getTableTypes().

     * Added paranoid parameter, which sanitizes error messages by
       removing "sensitive" information from them (such as host
       names, ports, or user names), as well as clearing "sensitive"
       data structures when possible.

A.4.18. Changes in MySQL Connector/J 3.0.0 (31 July 2002)

   Bugs fixed:

     * General source-code cleanup.

     * The driver now only works with JDK-1.2 or newer.

     * Fix and sort primary key names in DBMetaData (SF bugs 582086
       and 582086).

     * ResultSet.getTimestamp() now works for DATE
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html) types
       (SF bug 559134).

     * Float types now reported as java.sql.Types.FLOAT (SF bug
       579573).

     * Support for streaming (row-by-row) result sets (see README)
       Thanks to Doron.

     * Testsuite now uses Junit (which you can get from
       http://www.junit.org.

     * JDBC Compliance: Passes all tests besides stored procedure
       tests.

     * ResultSet.getDate/Time/Timestamp now recognizes all forms of
       invalid values that have been set to all zeros by MySQL (SF
       bug 586058).

     * Added multi-host failover support (see README).

     * Repackaging: New driver name is com.mysql.jdbc.Driver, old
       name still works, though (the driver is now provided by
       MySQL-AB).

     * Support for large packets (new addition to MySQL-4.0
       protocol), see README for more information.

     * Better checking for closed connections in Statement and
       PreparedStatement.

     * Performance improvements in string handling and field metadata
       creation (lazily instantiated) contributed by Alex
       Twisleton-Wykeham-Fiennes.

     * JDBC-3.0 functionality including
       Statement/PreparedStatement.getGeneratedKeys() and
       ResultSet.getURL().

     * Overall speed improvements via controlling transient object
       creation in MysqlIO class when reading packets.

     * !!! LICENSE CHANGE !!! The driver is now GPL. If you need
       non-GPL licenses, please contact me <mark@mysql.com>.

     * Performance enchancements: Driver is now 50-100% faster in
       most situations, and creates fewer temporary objects.

A.5. Changes in MySQL Connector/J 2.0.x

A.5.1. Changes in MySQL Connector/J 2.0.14 (16 May 2002)

   Bugs fixed:

     * ResultSet.getDouble() now uses code built into JDK to be more
       precise (but slower).

     * Fixed typo for relaxAutoCommit parameter.

     * LogicalHandle.isClosed() calls through to physical connection.

     * Added SQL profiling (to STDERR). Set profileSql=true in your
       JDBC URL. See README for more information.

     * PreparedStatement now releases resources on .close(). (SF bug
       553268)

     * More code cleanup.

     * Quoted identifiers not used if server version does not support
       them. Also, if server started with --ansi
       (http://dev.mysql.com/doc/refman/5.0/en/server-options.html#op
       tion_mysqld_ansi) or --sql-mode=ANSI_QUOTES
       (http://dev.mysql.com/doc/refman/5.0/en/server-options.html#op
       tion_mysqld_sql-mode), """ will be used as an identifier quote
       character, otherwise "'" will be used.

A.5.2. Changes in MySQL Connector/J 2.0.13 (24 April 2002)

   Bugs fixed:

     * Fixed unicode chars being read incorrectly. (SF bug 541088)

     * Faster blob escaping for PrepStmt.

     * Added setURL() to MySQLXADataSource. (SF bug 546019)

     * Added set/getPortNumber() to DataSource(s). (SF bug 548167)

     * PreparedStatement.toString() fixed. (SF bug 534026)

     * More code cleanup.

     * Rudimentary version of Statement.getGeneratedKeys() from
       JDBC-3.0 now implemented (you need to be using JDK-1.4 for
       this to work, I believe).

     * DBMetaData.getIndexInfo() - bad PAGES fixed. (SF BUG 542201)

     * ResultSetMetaData.getColumnClassName() now implemented.

A.5.3. Changes in MySQL Connector/J 2.0.12 (07 April 2002)

   Bugs fixed:

     * Fixed testsuite.Traversal afterLast() bug, thanks to Igor
       Lastric.

     * Added new types to getTypeInfo(), fixed existing types thanks
       to Al Davis and Kid Kalanon.

     * Fixed time zone off-by-1-hour bug in PreparedStatement
       (538286, 528785).

     * Added identifier quoting to all DatabaseMetaData methods that
       need them (should fix 518108).

     * Added support for BIT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)
       types (51870) to PreparedStatement.

     * ResultSet.insertRow() should now detect auto_increment fields
       in most cases and use that value in the new row. This
       detection will not work in multi-valued keys, however, due to
       the fact that the MySQL protocol does not return this
       information.

     * Relaxed synchronization in all classes, should fix 520615 and
       520393.

     * DataSources - fixed setUrl bug (511614, 525565), wrong
       datasource class name (532816, 528767).

     * Added support for YEAR
       (http://dev.mysql.com/doc/refman/5.0/en/year.html) type
       (533556).

     * Fixes for ResultSet updatability in PreparedStatement.

     * ResultSet: Fixed updatability (values being set to null if not
       updated).

     * Added getTable/ColumnPrivileges() to DBMD (fixes 484502).

     * Added getIdleFor() method to Connection and
       MysqlLogicalHandle.

     * ResultSet.refreshRow() implemented.

     * Fixed getRow() bug (527165) in ResultSet.

     * General code cleanup.

A.5.4. Changes in MySQL Connector/J 2.0.11 (27 January 2002)

   Bugs fixed:

     * Full synchronization of Statement.java.

     * Fixed missing DELETE_RULE value in
       DBMD.getImported/ExportedKeys() and getCrossReference().

     * More changes to fix Unexpected end of input stream errors when
       reading BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) values.
       This should be the last fix.

A.5.5. Changes in MySQL Connector/J 2.0.10 (24 January 2002)

   Bugs fixed:

     * Fixed null-pointer-exceptions when using
       MysqlConnectionPoolDataSource with Websphere 4 (bug 505839).

     * Fixed spurious Unexpected end of input stream errors in
       MysqlIO (bug 507456).

A.5.6. Changes in MySQL Connector/J 2.0.9 (13 January 2002)

   Bugs fixed:

     * Fixed extra memory allocation in MysqlIO.readPacket() (bug
       488663).

     * Added detection of network connection being closed when
       reading packets (thanks to Todd Lizambri).

     * Fixed casting bug in PreparedStatement (bug 488663).

     * DataSource implementations moved to
       org.gjt.mm.mysql.jdbc2.optional package, and (initial)
       implementations of PooledConnectionDataSource and XADataSource
       are in place (thanks to Todd Wolff for the implementation and
       testing of PooledConnectionDataSource with IBM WebSphere 4).

     * Fixed quoting error with escape processor (bug 486265).

     * Removed concatenation support from driver (the || operator),
       as older versions of VisualAge seem to be the only thing that
       use it, and it conflicts with the logical || operator. You
       will need to start mysqld with the --ansi
       (http://dev.mysql.com/doc/refman/5.0/en/server-options.html#op
       tion_mysqld_ansi) flag to use the || operator as concatenation
       (bug 491680).

     * Ant build was corrupting included jar files, fixed (bug
       487669).

     * Report batch update support through DatabaseMetaData (bug
       495101).

     * Implementation of DatabaseMetaData.getExported/ImportedKeys()
       and getCrossReference().

     * Fixed off-by-one-hour error in
       PreparedStatement.setTimestamp() (bug 491577).

     * Full synchronization on methods modifying instance and
       class-shared references, driver should be entirely thread-safe
       now (please let me know if you have problems).

A.5.7. Changes in MySQL Connector/J 2.0.8 (25 November 2001)

   Bugs fixed:

     * XADataSource/ConnectionPoolDataSource code (experimental)

     * DatabaseMetaData.getPrimaryKeys() and getBestRowIdentifier()
       are now more robust in identifying primary keys (matches
       regardless of case or abbreviation/full spelling of Primary
       Key in Key_type column).

     * Batch updates now supported (thanks to some inspiration from
       Daniel Rall).

     * PreparedStatement.setAnyNumericType() now handles positive
       exponents correctly (adds + so MySQL can understand it).

A.5.8. Changes in MySQL Connector/J 2.0.7 (24 October 2001)

   Bugs fixed:

     * Character sets read from database if useUnicode=true and
       characterEncoding is not set. (thanks to Dmitry Vereshchagin)

     * Initial transaction isolation level read from database (if
       available). (thanks to Dmitry Vereshchagin)

     * Fixed PreparedStatement generating SQL that would end up with
       syntax errors for some queries.

     * PreparedStatement.setCharacterStream() now implemented

     * Captialize type names when captializeTypeNames=true is passed
       in URL or properties (for WebObjects. (thanks to Anjo Krank)

     * ResultSet.getBlob() now returns null if column value was null.

     * Fixed ResultSetMetaData.getPrecision() returning one less than
       actual on newer versions of MySQL.

     * Fixed dangling socket problem when in high availability
       (autoReconnect=true) mode, and finalizer for Connection will
       close any dangling sockets on GC.

     * Fixed time zone issue in PreparedStatement.setTimestamp().
       (thanks to Erik Olofsson)

     * PreparedStatement.setDouble() now uses full-precision doubles
       (reverting a fix made earlier to truncate them).

     * Fixed DatabaseMetaData.supportsTransactions(), and
       supportsTransactionIsolationLevel() and getTypeInfo()
       SQL_DATETIME_SUB and SQL_DATA_TYPE fields not being readable.

     * Updatable result sets now correctly handle NULL values in
       fields.

     * PreparedStatement.setBoolean() will use 1/0 for values if your
       MySQL version is 3.21.23 or higher.

     * Fixed ResultSet.isAfterLast() always returning false.

A.5.9. Changes in MySQL Connector/J 2.0.6 (16 June 2001)

   Bugs fixed:

     * Fixed PreparedStatement parameter checking.

     * Fixed case-sensitive column names in ResultSet.java.

A.5.10. Changes in MySQL Connector/J 2.0.5 (13 June 2001)

   Bugs fixed:

     * ResultSet.insertRow() works now, even if not all columns are
       set (they will be set to NULL).

     * Added Byte to PreparedStatement.setObject().

     * Fixed data parsing of TIMESTAMP
       (http://dev.mysql.com/doc/refman/5.0/en/datetime.html) values
       with 2-digit years.

     * Added ISOLATION level support to
       Connection.setIsolationLevel()

     * DataBaseMetaData.getCrossReference() no longer ArrayIndexOOB.

     * ResultSet.getBoolean() now recognizes -1 as true.

     * ResultSet has +/-Inf/inf support.

     * getObject() on ResultSet correctly does TINYINT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)->B
       yte and SMALLINT
       (http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html)->S
       hort.

     * Fixed ResultSetMetaData.getColumnTypeName for TEXT
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html)/BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html).

     * Fixed ArrayIndexOutOfBounds when sending large BLOB
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) queries.
       (Max size packet was not being set)

     * Fixed NPE on PreparedStatement.executeUpdate() when all
       columns have not been set.

     * Fixed ResultSet.getBlob() ArrayIndex out-of-bounds.

A.5.11. Changes in MySQL Connector/J 2.0.3 (03 December 2000)

   Bugs fixed:

     * Fixed composite key problem with updatable result sets.

     * Faster ASCII string operations.

     * Fixed off-by-one error in java.sql.Blob implementation code.

     * Fixed incorrect detection of MAX_ALLOWED_PACKET, so sending
       large blobs should work now.

     * Added detection of -/+INF for doubles.

     * Added ultraDevHack URL parameter, set to true to allow
       (broken) Macromedia UltraDev to use the driver.

     * Implemented getBigDecimal() without scale component for JDBC2.

A.5.12. Changes in MySQL Connector/J 2.0.1 (06 April 2000)

   Bugs fixed:

     * Columns that are of type TEXT
       (http://dev.mysql.com/doc/refman/5.0/en/blob.html) now return
       as Strings when you use getObject().

     * Cleaned up exception handling when driver connects.

     * Fixed RSMD.isWritable() returning wrong value. Thanks to
       Moritz Maass.

     * DatabaseMetaData.getPrimaryKeys() now works correctly with
       respect to key_seq. Thanks to Brian Slesinsky.

     * Fixed many JDBC-2.0 traversal, positioning bugs, especially
       with respect to empty result sets. Thanks to Ron Smits, Nick
       Brook, Cessar Garcia and Carlos Martinez.

     * No escape processing is done on PreparedStatements anymore per
       JDBC spec.

     * Fixed some issues with updatability support in ResultSet when
       using multiple primary keys.

A.5.13. Changes in MySQL Connector/J 2.0.0pre5 (21 February 2000)


     * Fixed Bad Handshake problem.

A.5.14. Changes in MySQL Connector/J 2.0.0pre4 (10 January 2000)


     * Fixes to ResultSet for insertRow() - Thanks to Cesar Garcia

     * Fix to Driver to recognize JDBC-2.0 by loading a JDBC-2.0
       class, instead of relying on JDK version numbers. Thanks to
       John Baker.

     * Fixed ResultSet to return correct row numbers

     * Statement.getUpdateCount() now returns rows matched, instead
       of rows actually updated, which is more SQL-92 like.

   10-29-99

     * Statement/PreparedStatement.getMoreResults() bug fixed. Thanks
       to Noel J. Bergman.

     * Added Short as a type to PreparedStatement.setObject(). Thanks
       to Jeff Crowder

     * Driver now automagically configures maximum/preferred packet
       sizes by querying server.

     * Autoreconnect code uses fast ping command if server supports
       it.

     * Fixed various bugs with respect to packet sizing when reading
       from the server and when alloc'ing to write to the server.

A.5.15. Changes in MySQL Connector/J 2.0.0pre (17 August 1999)


     * Now compiles under JDK-1.2. The driver supports both JDK-1.1
       and JDK-1.2 at the same time through a core set of classes.
       The driver will load the appropriate interface classes at
       runtime by figuring out which JVM version you are using.

     * Fixes for result sets with all nulls in the first row.
       (Pointed out by Tim Endres)

     * Fixes to column numbers in SQLExceptions in ResultSet (Thanks
       to Blas Rodriguez Somoza)

     * The database no longer needs to specified to connect. (Thanks
       to Christian Motschke)

A.6. Changes in MySQL Connector/J 1.2b (04 July 1999)


     * Better Documentation (in progress), in doc/mm.doc/book1.html

     * DBMD now allows null for a column name pattern (not in spec),
       which it changes to '%'.

     * DBMD now has correct types/lengths for getXXX().

     * ResultSet.getDate(), getTime(), and getTimestamp() fixes.
       (contributed by Alan Wilken)

     * EscapeProcessor now handles \{ \} and { or } inside quotes
       correctly. (thanks to Alik for some ideas on how to fix it)

     * Fixes to properties handling in Connection. (contributed by
       Juho Tikkala)

     * ResultSet.getObject() now returns null for NULL columns in the
       table, rather than bombing out. (thanks to Ben Grosman)

     * ResultSet.getObject() now returns Strings for types from MySQL
       that it doesn't know about. (Suggested by Chris Perdue)

     * Removed DataInput/Output streams, not needed, 1/2 number of
       method calls per IO operation.

     * Use default character encoding if one is not specified. This
       is a work-around for broken JVMs, because according to spec,
       EVERY JVM must support "ISO8859_1", but they do not.

     * Fixed Connection to use the platform character encoding
       instead of "ISO8859_1" if one isn't explicitly set. This fixes
       problems people were having loading the character- converter
       classes that didn't always exist (JVM bug). (thanks to Fritz
       Elfert for pointing out this problem)

     * Changed MysqlIO to re-use packets where possible to reduce
       memory usage.

     * Fixed escape-processor bugs pertaining to {} inside quotes.

A.7. Changes in MySQL Connector/J 1.2.x and lower

A.7.1. Changes in MySQL Connector/J 1.2a (14 April 1999)


     * Fixed character-set support for non-Javasoft JVMs (thanks to
       many people for pointing it out)

     * Fixed ResultSet.getBoolean() to recognize 'y' & 'n' as well as
       '1' & '0' as boolean flags. (thanks to Tim Pizey)

     * Fixed ResultSet.getTimestamp() to give better performance.
       (thanks to Richard Swift)

     * Fixed getByte() for numeric types. (thanks to Ray Bellis)

     * Fixed DatabaseMetaData.getTypeInfo() for DATE type. (thanks to
       Paul Johnston)

     * Fixed EscapeProcessor for "fn" calls. (thanks to Piyush Shah
       at locomotive.org)

     * Fixed EscapeProcessor to not do extraneous work if there are
       no escape codes. (thanks to Ryan Gustafson)

     * Fixed Driver to parse URLs of the form
       "jdbc:mysql://host:port" (thanks to Richard Lobb)

A.7.2. Changes in MySQL Connector/J 1.1i (24 March 1999)


     * Fixed Timestamps for PreparedStatements

     * Fixed null pointer exceptions in RSMD and RS

     * Re-compiled with jikes for valid class files (thanks ms!)

A.7.3. Changes in MySQL Connector/J 1.1h (08 March 1999)


     * Fixed escape processor to deal with unmatched { and } (thanks
       to Craig Coles)

     * Fixed escape processor to create more portable (between
       DATETIME and TIMESTAMP types) representations so that it will
       work with BETWEEN clauses. (thanks to Craig Longman)

     * MysqlIO.quit() now closes the socket connection. Before, after
       many failed connections some OS's would run out of file
       descriptors. (thanks to Michael Brinkman)

     * Fixed NullPointerException in Driver.getPropertyInfo. (thanks
       to Dave Potts)

     * Fixes to MysqlDefs to allow all *text fields to be retrieved
       as Strings. (thanks to Chris at Leverage)

     * Fixed setDouble in PreparedStatement for large numbers to
       avoid sending scientific notation to the database. (thanks to
       J.S. Ferguson)

     * Fixed getScale() and getPrecision() in RSMD. (contrib'd by
       James Klicman)

     * Fixed getObject() when field was DECIMAL or NUMERIC (thanks to
       Bert Hobbs)

     * DBMD.getTables() bombed when passed a null table-name pattern.
       Fixed. (thanks to Richard Lobb)

     * Added check for "client not authorized" errors during connect.
       (thanks to Hannes Wallnoefer)

A.7.4. Changes in MySQL Connector/J 1.1g (19 February 1999)


     * Result set rows are now byte arrays. Blobs and Unicode work
       bidriectonally now. The useUnicode and encoding options are
       implemented now.

     * Fixes to PreparedStatement to send binary set by setXXXStream
       to be sent untouched to the MySQL server.

     * Fixes to getDriverPropertyInfo().

A.7.5. Changes in MySQL Connector/J 1.1f (31 December 1998)


     * Changed all ResultSet fields to Strings, this should allow
       Unicode to work, but your JVM must be able to convert between
       the character sets. This should also make reading data from
       the server be a bit quicker, because there is now no
       conversion from StringBuffer to String.

     * Changed PreparedStatement.streamToString() to be more
       efficient (code from Uwe Schaefer).

     * URL parsing is more robust (throws SQL exceptions on errors
       rather than NullPointerExceptions)

     * PreparedStatement now can convert Strings to Time/Date values
       via setObject() (code from Robert Currey).

     * IO no longer hangs in Buffer.readInt(), that bug was
       introduced in 1.1d when changing to all byte-arrays for result
       sets. (Pointed out by Samo Login)

A.7.6. Changes in MySQL Connector/J 1.1b (03 November 1998)


     * Fixes to DatabaseMetaData to allow both IBM VA and J-Builder
       to work. Let me know how it goes. (thanks to Jac Kersing)

     * Fix to ResultSet.getBoolean() for NULL strings (thanks to
       Barry Lagerweij)

     * Beginning of code cleanup, and formatting. Getting ready to
       branch this off to a parallel JDBC-2.0 source tree.

     * Added "final" modifier to critical sections in MysqlIO and
       Buffer to allow compiler to inline methods for speed.

   9-29-98

     * If object references passed to setXXX() in PreparedStatement
       are null, setNull() is automatically called for you. (Thanks
       for the suggestion goes to Erik Ostrom)

     * setObject() in PreparedStatement will now attempt to write a
       serialized representation of the object to the database for
       objects of Types.OTHER and objects of unknown type.

     * Util now has a static method readObject() which given a
       ResultSet and a column index will re-instantiate an object
       serialized in the above manner.

A.7.7. Changes in MySQL Connector/J 1.1 (02 September 1998)


     * Got rid of "ugly hack" in MysqlIO.nextRow(). Rather than catch
       an exception, Buffer.isLastDataPacket() was fixed.

     * Connection.getCatalog() and Connection.setCatalog() should
       work now.

     * Statement.setMaxRows() works, as well as setting by property
       maxRows. Statement.setMaxRows() overrides maxRows set via
       properties or url parameters.

     * Automatic re-connection is available. Because it has to "ping"
       the database before each query, it is turned off by default.
       To use it, pass in "autoReconnect=true" in the connection URL.
       You may also change the number of reconnect tries, and the
       initial timeout value via "maxReconnects=n" (default 3) and
       "initialTimeout=n" (seconds, default 2) parameters. The
       timeout is an exponential backoff type of timeout; for
       example, if you have initial timeout of 2 seconds, and
       maxReconnects of 3, then the driver will timeout 2 seconds, 4
       seconds, then 16 seconds between each re-connection attempt.

A.7.8. Changes in MySQL Connector/J 1.0 (24 August 1998)


     * Fixed handling of blob data in Buffer.java

     * Fixed bug with authentication packet being sized too small.

     * The JDBC Driver is now under the LPGL

   8-14-98

     * Fixed Buffer.readLenString() to correctly read data for BLOBS.

     * Fixed PreparedStatement.stringToStream to correctly read data
       for BLOBS.

     * Fixed PreparedStatement.setDate() to not add a day. (above
       fixes thanks to Vincent Partington)

     * Added URL parameter parsing (?user=... and so forth).

A.7.9. Changes in MySQL Connector/J 0.9d (04 August 1998)


     * Big news! New package name. Tim Endres from ICE Engineering is
       starting a new source tree for GNU GPL'd Java software. He's
       graciously given me the org.gjt.mm package directory to use,
       so now the driver is in the org.gjt.mm.mysql package scheme.
       I'm "legal" now. Look for more information on Tim's project
       soon.

     * Now using dynamically sized packets to reduce memory usage
       when sending commands to the DB.

     * Small fixes to getTypeInfo() for parameters, and so forth.

     * DatabaseMetaData is now fully implemented. Let me know if
       these drivers work with the various IDEs out there. I've heard
       that they're working with JBuilder right now.

     * Added JavaDoc documentation to the package.

     * Package now available in .zip or .tar.gz.

A.7.10. Changes in MySQL Connector/J 0.9 (28 July 1998)


     * Implemented getTypeInfo(). Connection.rollback() now throws an
       SQLException per the JDBC spec.

     * Added PreparedStatement that supports all JDBC API methods for
       PreparedStatement including InputStreams. Please check this
       out and let me know if anything is broken.

     * Fixed a bug in ResultSet that would break some queries that
       only returned 1 row.

     * Fixed bugs in DatabaseMetaData.getTables(),
       DatabaseMetaData.getColumns() and
       DatabaseMetaData.getCatalogs().

     * Added functionality to Statement that allows executeUpdate()
       to store values for IDs that are automatically generated for
       AUTO_INCREMENT fields. Basically, after an executeUpdate(),
       look at the SQLWarnings for warnings like "LAST_INSERTED_ID =
       'some number', COMMAND = 'your SQL query'". If you are using
       AUTO_INCREMENT fields in your tables and are executing a lot
       of executeUpdate()s on one Statement, be sure to
       clearWarnings() every so often to save memory.

A.7.11. Changes in MySQL Connector/J 0.8 (06 July 1998)


     * Split MysqlIO and Buffer to separate classes. Some
       ClassLoaders gave an IllegalAccess error for some fields in
       those two classes. Now mm.mysql works in applets and all
       classloaders. Thanks to Joe Ennis <jce@mail.boone.com> for
       pointing out the problem and working on a fix with me.

A.7.12. Changes in MySQL Connector/J 0.7 (01 July 1998)


     * Fixed DatabaseMetadata problems in getColumns() and bug in
       switch statement in the Field constructor. Thanks to Costin
       Manolache <costin@tdiinc.com> for pointing these out.

A.7.13. Changes in MySQL Connector/J 0.6 (21 May 1998)


     * Incorporated efficiency changes from Richard Swift
       <Richard.Swift@kanatek.ca> in MysqlIO.java and ResultSet.java:

     * We're now 15% faster than gwe's driver.

     * Started working on DatabaseMetaData.

     * The following methods are implemented:

          + getTables()

          + getTableTypes()

          + getColumns()

          + getCatalogs()