create_database(7)

NAME#

CREATE_DATABASE - create a new database

SYNOPSIS#

CREATE DATABASE \nname\n
\n
    [ WITH ] [ OWNER [=] \nuser_name\n ]
\n
           [ TEMPLATE [=] \ntemplate\n ]
\n
           [ ENCODING [=] \nencoding\n ]
\n
           [ STRATEGY [=] \nstrategy\n ]
\n
           [ LOCALE [=] \nlocale\n ]
\n
           [ LC_COLLATE [=] \nlc_collate\n ]
\n
           [ LC_CTYPE [=] \nlc_ctype\n ]
\n
           [ BUILTIN_LOCALE [=] \nbuiltin_locale\n ]
\n
           [ ICU_LOCALE [=] \nicu_locale\n ]
\n
           [ ICU_RULES [=] \nicu_rules\n ]
\n
           [ LOCALE_PROVIDER [=] \nlocale_provider\n ]
\n
           [ COLLATION_VERSION = \ncollation_version\n ]
\n
           [ TABLESPACE [=] \ntablespace_name\n ]
\n
           [ ALLOW_CONNECTIONS [=] \nallowconn\n ]
\n
           [ CONNECTION LIMIT [=] \nconnlimit\n ]
\n
           [ IS_TEMPLATE [=] \nistemplate\n ]
\n
           [ OID [=] \noid\n ]

DESCRIPTION#

CREATE DATABASE creates a new PostgreSQL database.

To create a database, you must be a superuser or have the special CREATEDB privilege. See CREATE ROLE (CREATE_ROLE(7)).

By default, the new database will be created by cloning the standard system database template1. A different template can be specified by writing TEMPLATE name. In particular, by writing TEMPLATE template0, you can create a pristine database (one where no user-defined objects exist and where the system objects have not been altered) containing only the standard objects predefined by your version of PostgreSQL. This is useful if you wish to avoid copying any installation-local objects that might have been added to template1.

PARAMETERS#

name

user_name

template

encoding

strategy

locale

Can be overridden by setting lc_collate, lc_ctype, builtin_locale, or icu_locale individually.

If locale_provider is builtin, then locale or builtin_locale must be specified and set to either C or C.UTF-8.

lc_collate

If locale_provider is libc, also sets the default collation order to use in the new database, overriding the setting locale.

lc_ctype

If locale_provider is libc, also sets the default character classification to use in the new database, overriding the setting locale.

builtin_locale

The locales available for the builtin provider are C and C.UTF-8.

icu_locale

icu_rules

locale_provider

collation_version

See also ALTER DATABASE (ALTER_DATABASE(7)) for how to handle database collation version mismatches.

tablespace_name

allowconn

connlimit

istemplate

oid

Optional parameters can be written in any order, not only the order illustrated above.

NOTES#

CREATE DATABASE cannot be executed inside a transaction block.

Errors along the line of “could not initialize database directory” are most likely related to insufficient permissions on the data directory, a full disk, or other file system problems.

Use DROP DATABASE to remove a database.

The program createdb(1) is a wrapper program around this command, provided for convenience.

Database-level configuration parameters (set via ALTER DATABASE) and database-level permissions (set via GRANT) are not copied from the template database.

Although it is possible to copy a database other than template1 by specifying its name as the template, this is not (yet) intended as a general-purpose “COPY DATABASE” facility. The principal limitation is that no other sessions can be connected to the template database while it is being copied. CREATE DATABASE will fail if any other connection exists when it starts; otherwise, new connections to the template database are locked out until CREATE DATABASE completes. See Section 22.3 for more information.

The character set encoding specified for the new database must be compatible with the chosen locale settings (LC_COLLATE and LC_CTYPE). If the locale is C (or equivalently POSIX), then all encodings are allowed, but for other locale settings there is only one encoding that will work properly. (On Windows, however, UTF-8 encoding can be used with any locale.) CREATE DATABASE will allow superusers to specify SQL_ASCII encoding regardless of the locale settings, but this choice is deprecated and may result in misbehavior of character-string functions if data that is not encoding-compatible with the locale is stored in the database.

The encoding and locale settings must match those of the template database, except when template0 is used as template. This is because other databases might contain data that does not match the specified encoding, or might contain indexes whose sort ordering is affected by LC_COLLATE and LC_CTYPE. Copying such data would result in a database that is corrupt according to the new settings. template0, however, is known to not contain any data or indexes that would be affected.

There is currently no option to use a database locale with nondeterministic comparisons (see CREATE COLLATION for an explanation). If this is needed, then per-column collations would need to be used.

The CONNECTION LIMIT option is only enforced approximately; if two new sessions start at about the same time when just one connection “slot” remains for the database, it is possible that both will fail. Also, the limit is not enforced against superusers or background worker processes.

EXAMPLES#

To create a new database:

CREATE DATABASE lusiadas;

To create a database sales owned by user salesapp with a default tablespace of salesspace:

CREATE DATABASE sales OWNER salesapp TABLESPACE salesspace;

To create a database music with a different locale:

CREATE DATABASE music
\n
    LOCALE 'sv_SE.utf8'
\n
    TEMPLATE template0;

In this example, the TEMPLATE template0 clause is required if the specified locale is different from the one in template1. (If it is not, then specifying the locale explicitly is redundant.)

To create a database music2 with a different locale and a different character set encoding:

CREATE DATABASE music2
\n
    LOCALE 'sv_SE.iso885915'
\n
    ENCODING LATIN9
\n
    TEMPLATE template0;

The specified locale and encoding settings must match, or an error will be reported.

Note that locale names are specific to the operating system, so that the above commands might not work in the same way everywhere.

COMPATIBILITY#

There is no CREATE DATABASE statement in the SQL standard. Databases are equivalent to catalogs, whose creation is implementation-defined.

SEE ALSO#

ALTER DATABASE (ALTER_DATABASE(7)), DROP DATABASE (DROP_DATABASE(7))