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<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
<link rel="STYLESHEET" type="text/css" href="pgadmin3.css">
<title>pgAdmin Query Tool</title>
</head>
<body>
<H3>pgAdmin Query Tool</H3>
<center><img src="images/query.png"></center>
<P>The Query Tool enables you to execute arbitrary SQL commands. All
rules that are mentioned in the PostgreSQL User's guide apply.
</P>
<P>The upper part of the Query Tool contains the edit entry window,
where you type your commands. You may read the query from a file, or
write it out to a file. When writing a file, the encoding of the file
is determined by the file suffix: if it is *.sql, a 8 byte local
character set is used. If *.usql is selected, the file will be
written in UTF-8, which enables the storage of virtually all
characters used throughout the world, according to the coding rules
of the <A HREF="http://www.unicode.org/">Unicode Consortium</A>. If
you select *.*, the setting from the <A HREF="options-tab2.html">read/write
unicode option</A> is used.</P>
<P>To execute the query, you select Execute from the Query menu, or
you press the execute toolbar button, or you press the F5 function
key. If you didn't select a word, the complete contents of the window
will be sent to the database server, which executes it. You may also
execute just a part of the text, by selecting only the text that you
want the server to execute.</P>
<P>Explain from the Query menu, or F7 function key will execute the
EXPLAIN command. The database server will analyze the query that's
sent to it, and will return the results.
</P><P>
<center><img src="images/query-analyze.png"></center>
</P><P>
The result is displayed as text in the Data Output page, and graphically
visualized on the Explain page. This enables you to find out how the query is parsed, optimized and executed. You can modify the
degree of inspection by changing the Explain options for this in the
Query menu. Please note that "EXPLAIN VERBOSE" can not be displayed graphically.</P>
<P>In case the query you sent to the server using the Execute or
Explain command takes longer than you expect, and you would like to
abort the execution, you can select Cancel from the Query menu, press
the Cancel toolbar button or use Alt-Break function key to abort the
execution.
</P>
<P>If you want to have help about a SQL command you want to execute,
you can mark a SQL keyword and select SQL Help from the Help menu,
the SQL Help toolbar button or simply press the F1 key. pgAdmin III
will try to locate the appropriate information in the PostgreSQL
documentation for you.</P>
<P>The result of the database server execution will be displayed in
the lower part of the Query Tool. If the last command in the chain of
SQL command sent to the server was as command returning a result set,
this will be shown on the Data Output page. All rowsets from previous
commands will be discarded.</P>
<P>To save the data in the Data Output page to a file, you can use
the <A HREF="export.html">Export</A> dialog.
</P>
<P>Information about all commands just executed will go to the
Messages page. The History page will remember all commands executed
and the results from this, until you use Clear History from the Query
menu to clear the window. If you want to retain the history for later
inspection, you can save the contents of the History page to a file
using the Save history option from the Query menu.</P>
<P>The status line will show how long the last query took to
complete. If a dataset was returned, not only the elapsed time for
server execution is displayed, but also the time to retrieve the data
from the server to the Data Output page.</P>
<P>
In the toolbar combobox you can quickly change your database connection from
one database to another, without launching another instance of the query tool.
Initially, only one database will be available, but by selecting &less;new connection> from
the combobox, you can add another connection to it.
</P><P>
<center><img src="images/query-connect.png"></center>
</P>
<P>In the <A HREF="options-tab3.html">options dialog</A>, you
can specify a default limit for the rowset size to retrieve. By
default, this value will be 100. If the number of rows to retrieve
from the server exceeds this value, a message box will appear asking
what to do to prevent retrieval of an unexpected high amount of data.
You may decide to retrieve just the first rows, as configured with
tha max rows setting, or retrieving the complete rowset regardless of
the setting, or abort the query, effectively retrieving zero rows.</P>
</BODY>
</HTML>
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