Every table has several system columns that are implicitly defined by the system. Therefore, these names cannot be used as names of user-defined columns. (Note that these restrictions are separate from whether the name is a key word or not; quoting a name will not allow you to escape these restrictions.) You do not really need to be concerned about these columns; just know they exist. oid The object identifier (object ID) of a row. This column is only present if the table was created using WI

Error, warning, and log messages generated within the server code should be created using ereport, or its older cousin elog. The use of this function is complex enough to require some explanation. There are two required elements for every message: a severity level (ranging from DEBUG to PANIC) and a primary message text. In addition there are optional elements, the most common of which is an error identifier code that follows the SQL spec's SQLSTATE conventions. ereport itself is just a shell f

NameALTER FOREIGN DATA WRAPPER -- change the definition of a foreign-data wrapper Synopsis ALTER FOREIGN DATA WRAPPER name [ HANDLER handler_function | NO HANDLER ] [ VALIDATOR validator_function | NO VALIDATOR ] [ OPTIONS ( [ ADD | SET | DROP ] option ['value'] [, ... ]) ] ALTER FOREIGN DATA WRAPPER name OWNER TO { new_owner | CURRENT_USER | SESSION_USER } ALTER FOREIGN DATA WRAPPER name RENAME TO new_name Description ALTER FOREIGN DATA WRAPPER changes the definition of a

NameCREATE FOREIGN TABLE -- define a new foreign table Synopsis CREATE FOREIGN TABLE [ IF NOT EXISTS ] table_name ( [ { column_name data_type [ OPTIONS ( option 'value' [, ... ] ) ] [ COLLATE collation ] [ column_constraint [ ... ] ] | table_constraint } [, ... ] ] ) [ INHERITS ( parent_table [, ... ] ) ] SERVER server_name [ OPTIONS ( option 'value' [, ... ] ) ] where column_constraint is: [ CONSTRAINT constraint_name ] { NOT NULL | NULL | CHECK ( expression ) [ NO INHE

The INSERT statement is used to populate a table with rows: INSERT INTO weather VALUES ('San Francisco', 46, 50, 0.25, '1994-11-27'); Note that all data types use rather obvious input formats. Constants that are not simple numeric values usually must be surrounded by single quotes ('), as in the example. The date type is actually quite flexible in what it accepts, but for this tutorial we will stick to the unambiguous format shown here. The point type requires a coordinate pair as input, as s

Namepg_ctl -- initialize, start, stop, or control a PostgreSQL server Synopsis pg_ctl init[db] [-s] [-D datadir] [-o initdb-options] pg_ctl start [-w] [-t seconds] [-s] [-D datadir] [-l filename] [-o options] [-p path] [-c] pg_ctl stop [-W] [-t seconds] [-s] [-D datadir] [-m s[mart] | f[ast] | i[mmediate] ] pg_ctl restart [-w] [-t seconds] [-s] [-D datadir] [-c] [-m s[mart] | f[ast] | i[mmediate] ] [-o options] pg_ctl reload [-s] [-D datadir] pg_ctl status [-D datadir] pg_ctl promote [-s]

Because each worker executes the parallel portion of the plan to completion, it is not possible to simply take an ordinary query plan and run it using multiple workers. Each worker would produce a full copy of the output result set, so the query would not run any faster than normal but would produce incorrect results. Instead, the parallel portion of the plan must be what is known internally to the query optimizer as a partial plan; that is, it must constructed so that each process will which e

NameALTER TEXT SEARCH DICTIONARY -- change the definition of a text search dictionary Synopsis ALTER TEXT SEARCH DICTIONARY name ( option [ = value ] [, ... ] ) ALTER TEXT SEARCH DICTIONARY name RENAME TO new_name ALTER TEXT SEARCH DICTIONARY name OWNER TO { new_owner | CURRENT_USER | SESSION_USER } ALTER TEXT SEARCH DICTIONARY name SET SCHEMA new_schema Description ALTER TEXT SEARCH DICTIONARY changes the definition of a text search dictionary. You can change the dictionary's tem

The pg_stat_statements module provides a means for tracking execution statistics of all SQL statements executed by a server. The module must be loaded by adding pg_stat_statements to shared_preload_libraries in postgresql.conf, because it requires additional shared memory. This means that a server restart is needed to add or remove the module. When pg_stat_statements is loaded, it tracks statistics across all databases of the server. To access and manipulate these statistics, the module provide

NameCREATE TRANSFORM -- define a new transform Synopsis CREATE [ OR REPLACE ] TRANSFORM FOR type_name LANGUAGE lang_name ( FROM SQL WITH FUNCTION from_sql_function_name (argument_type [, ...]), TO SQL WITH FUNCTION to_sql_function_name (argument_type [, ...]) ); Description CREATE TRANSFORM defines a new transform. CREATE OR REPLACE TRANSFORM will either create a new transform, or replace an existing definition. A transform specifies how to adapt a data type to a procedural la