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ALTER DATABASE
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ALTER DATABASE

ALTER DATABASE — change a database

Synopsis

ALTER DATABASEname [ [ WITH ]option [ ... ] ]whereoption can be:    ALLOW_CONNECTIONSallowconn    CONNECTION LIMITconnlimit    IS_TEMPLATEistemplateALTER DATABASEname RENAME TOnew_nameALTER DATABASEname OWNER TO {new_owner | CURRENT_ROLE | CURRENT_USER | SESSION_USER }ALTER DATABASEname SET TABLESPACEnew_tablespaceALTER DATABASEname REFRESH COLLATION VERSIONALTER DATABASEname SETconfiguration_parameter { TO | = } {value | DEFAULT }ALTER DATABASEname SETconfiguration_parameter FROM CURRENTALTER DATABASEname RESETconfiguration_parameterALTER DATABASEname RESET ALL

Description

ALTER DATABASE changes the attributes of a database.

The first form changes certain per-database settings. (See below for details.) Only the database owner or a superuser can change these settings.

The second form changes the name of the database. Only the database owner or a superuser can rename a database; non-superuser owners must also have theCREATEDB privilege. The current database cannot be renamed. (Connect to a different database if you need to do that.)

The third form changes the owner of the database. To alter the owner, you must be able toSET ROLE to the new owning role, and you must have theCREATEDB privilege. (Note that superusers have all these privileges automatically.)

The fourth form changes the default tablespace of the database. Only the database owner or a superuser can do this; you must also have create privilege for the new tablespace. This command physically moves any tables or indexes in the database's old default tablespace to the new tablespace. The new default tablespace must be empty for this database, and no one can be connected to the database. Tables and indexes in non-default tablespaces are unaffected.

The remaining forms change the session default for a run-time configuration variable for aPostgres Pro database. Whenever a new session is subsequently started in that database, the specified value becomes the session default value. The database-specific default overrides whatever setting is present inpostgresql.conf or has been received from thepostgres command line. Only the database owner or a superuser can change the session defaults for a database. Certain variables cannot be set this way, or can only be set by a superuser.

Parameters

name

The name of the database whose attributes are to be altered.

allowconn

If false then no one can connect to this database.

connlimit

How many concurrent connections can be made to this database. -1 means no limit.

istemplate

If true, then this database can be cloned by any user withCREATEDB privileges; if false, then only superusers or the owner of the database can clone it.

new_name

The new name of the database.

new_owner

The new owner of the database.

new_tablespace

The new default tablespace of the database.

This form of the command cannot be executed inside a transaction block.

REFRESH COLLATION VERSION

Update the database collation version. SeeNotes for background.

configuration_parameter value

Set this database's session default for the specified configuration parameter to the given value. Ifvalue isDEFAULT or, equivalently,RESET is used, the database-specific setting is removed, so the system-wide default setting will be inherited in new sessions. UseRESET ALL to clear all database-specific settings.SET FROM CURRENT saves the session's current value of the parameter as the database-specific value.

SeeSET andChapter 18 for more information about allowed parameter names and values.

Notes

It is also possible to tie a session default to a specific role rather than to a database; seeALTER ROLE. Role-specific settings override database-specific ones if there is a conflict.

Examples

To disable index scans by default in the databasetest:

ALTER DATABASE test SET enable_indexscan TO off;

Compatibility

TheALTER DATABASE statement is aPostgres Pro extension.