pg — The Classic PyGreSQL Interface

Contents

• Introduction
• Module functions and constants
  • connect – Open a PostgreSQL connection
  • get/set_defhost – default server host [DV]
  • get/set_defport – default server port [DV]
  • get/set_defopt – default connection options [DV]
  • get/set_defbase – default database name [DV]
  • get/set_defuser – default database user [DV]
  • get/set_defpasswd – default database password [DV]
  • escape_string – escape a string for use within SQL
  • escape_bytea – escape binary data for use within SQL
  • unescape_bytea – unescape data that has been retrieved as text
  • get/set_namedresult – conversion to named tuples
  • get/set_decimal – decimal type to be used for numeric values
  • get/set_decimal_point – decimal mark used for monetary values
  • get/set_bool – whether boolean values are returned as bool objects
  • get/set_array – whether arrays are returned as list objects
  • get/set_bytea_escaped – whether bytea data is returned escaped
  • get/set_jsondecode – decoding JSON format
  • get/set_cast_hook – fallback typecast function
  • get/set_datestyle – assume a fixed date style
  • get/set_typecast – custom typecasting
  • cast_array/record – fast parsers for arrays and records
  • Type helpers
  • Module constants
• Connection – The connection object
  • query – execute a SQL command string
  • reset – reset the connection
  • cancel – abandon processing of current SQL command
  • close – close the database connection
  • transaction – get the current transaction state
  • parameter – get a current server parameter setting
  • date_format – get the currently used date format
  • fileno – get the socket used to connect to the database
  • getnotify – get the last notify from the server
  • inserttable – insert a list into a table
  • get/set_notice_receiver – custom notice receiver
  • putline – write a line to the server socket [DA]
  • getline – get a line from server socket [DA]
  • endcopy – synchronize client and server [DA]
  • locreate – create a large object in the database [LO]
  • getlo – build a large object from given oid [LO]
  • loimport – import a file to a large object [LO]
  • Object attributes
• The DB wrapper class
  • Initialization
  • pkey – return the primary key of a table
  • get_databases – get list of databases in the system
  • get_relations – get list of relations in connected database
  • get_tables – get list of tables in connected database
  • get_attnames – get the attribute names of a table
  • has_table_privilege – check table privilege
  • get/set_parameter – get or set run-time parameters
  • begin/commit/rollback/savepoint/release – transaction handling
  • get – get a row from a database table or view
  • insert – insert a row into a database table
  • update – update a row in a database table
  • upsert – insert a row with conflict resolution
  • query – execute a SQL command string
  • query_formatted – execute a formatted SQL command string
  • clear – clear row values in memory
  • delete – delete a row from a database table
  • truncate – quickly empty database tables
  • get_as_list/dict – read a table as a list or dictionary
  • escape_literal/identifier/string/bytea – escape for SQL
  • unescape_bytea – unescape data retrieved from the database
  • encode/decode_json – encode and decode JSON data
  • use_regtypes – determine use of regular type names
  • notification_handler – create a notification handler
  • Attributes of the DB wrapper class
• Query methods
  • getresult – get query values as list of tuples
  • dictresult – get query values as list of dictionaries
  • namedresult – get query values as list of named tuples
  • listfields – list fields names of previous query result
  • fieldname, fieldnum – field name/number conversion
  • ntuples – return number of tuples in query object
• LargeObject – Large Objects
  • open – open a large object
  • close – close a large object
  • read, write, tell, seek, unlink – file-like large object handling
  • size – get the large object size
  • export – save a large object to a file
  • Object attributes
• The Notification Handler
  • Instantiating the notification handler
  • Invoking the notification handler
  • Sending notifications
  • Auxiliary methods
• DbTypes – The internal cache for database types
• Remarks on Adaptation and Typecasting
  • Supported data types
  • Adaptation of parameters
  • Typecasting to Python