ALTER DATABASE

ALTER DATABASE

7

SQL - Language Statements

ALTER DATABASE

change a database

ALTER DATABASE

name

\[ \[ WITH \]

option

\[ \... \] \]

where

option

can be:

ALLOW\_CONNECTIONS

allowconn

CONNECTION LIMIT

connlimit

IS\_TEMPLATE

istemplate

ALTER DATABASE

name

RENAME TO

new\_name

ALTER DATABASE

name

OWNER TO {

new\_owner

\| CURRENT\_ROLE \| CURRENT\_USER \| SESSION\_USER } ALTER DATABASE

name

SET TABLESPACE

new\_tablespace

ALTER DATABASE

name

REFRESH COLLATION VERSION ALTER DATABASE

name

SET

configuration\_parameter

{ TO \| = } {

value

\| DEFAULT } ALTER DATABASE

name

SET

configuration\_parameter

FROM CURRENT ALTER DATABASE

name

RESET

configuration\_parameter

ALTER DATABASE

name

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 the `CREATEDB` 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 own the database and also be a direct or indirect member of the
new owning role, and you must have the `CREATEDB` 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 a PostgreSQL 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 in `postgresql.conf` or has been received
from the `postgres` 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 with
    `CREATEDB` 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. See
    [???](#sql-altercollation-notes) for background.

configuration\_parameter; value

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

    See [???](#sql-set) and [???](#runtime-config) 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; see [???](#sql-alterrole). Role-specific settings
override database-specific ones if there is a conflict.

Examples
========

To disable index scans by default in the database `test`:

    ALTER DATABASE test SET enable_indexscan TO off;

Compatibility
=============

The `ALTER DATABASE` statement is a PostgreSQL extension.

See Also
========
