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CREATE DATABASE(7) PostgreSQL 12.3 Documentation CREATE DATABASE(7)
NAME
CREATE_DATABASE - create a new database
SYNOPSIS
CREATE DATABASE name
[ [ WITH ] [ OWNER [=] user_name ]
[ TEMPLATE [=] template ]
[ ENCODING [=] encoding ]
[ LC_COLLATE [=] lc_collate ]
[ LC_CTYPE [=] lc_ctype ]
[ TABLESPACE [=] tablespace_name ]
[ ALLOW_CONNECTIONS [=] allowconn ]
[ CONNECTION LIMIT [=] connlimit ]
[ IS_TEMPLATE [=] istemplate ] ]
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 virgin database 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
The name of a database to create.
user_name
The role name of the user who will own the new database, or DEFAULT to use the default
(namely, the user executing the command). To create a database owned by another role,
you must be a direct or indirect member of that role, or be a superuser.
template
The name of the template from which to create the new database, or DEFAULT to use the
default template (template1).
encoding
Character set encoding to use in the new database. Specify a string constant (e.g.,
'SQL_ASCII'), or an integer encoding number, or DEFAULT to use the default encoding
(namely, the encoding of the template database). The character sets supported by the
PostgreSQL server are described in Section 23.3.1. See below for additional
restrictions.
lc_collate
Collation order (LC_COLLATE) to use in the new database. This affects the sort order
applied to strings, e.g. in queries with ORDER BY, as well as the order used in
indexes on text columns. The default is to use the collation order of the template
database. See below for additional restrictions.
lc_ctype
Character classification (LC_CTYPE) to use in the new database. This affects the
categorization of characters, e.g. lower, upper and digit. The default is to use the
character classification of the template database. See below for additional
restrictions.
tablespace_name
The name of the tablespace that will be associated with the new database, or DEFAULT
to use the template database's tablespace. This tablespace will be the default
tablespace used for objects created in this database. See CREATE TABLESPACE
(CREATE_TABLESPACE(7)) for more information.
allowconn
If false then no one can connect to this database. The default is true, allowing
connections (except as restricted by other mechanisms, such as GRANT/REVOKE CONNECT).
connlimit
How many concurrent connections can be made to this database. -1 (the default) means
no limit.
istemplate
If true, then this database can be cloned by any user with CREATEDB privileges; if
false (the default), then only superusers or the owner of the database can clone it.
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 (DROP_DATABASE(7)) 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 (ALTER_DATABASE(7))) 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.
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
LC_COLLATE 'sv_SE.utf8' LC_CTYPE 'sv_SE.utf8'
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
LC_COLLATE 'sv_SE.iso885915' LC_CTYPE 'sv_SE.iso885915'
ENCODING LATIN9
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))
PostgreSQL 12.3 2020 CREATE DATABASE(7)
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