PostgreSQL - SQL Language Reference

PostgreSQL Reference Manual - Volume 1 - SQL Language Reference
by The PostgreSQL Global Development Group
Paperback (6"x9"), 716 pages
ISBN 0954612027
RRP £32.00 ($49.95)

Sales of this book support the PostgreSQL project! Get a printed copy>>>

PostgreSQL Reference Manual
Volume 1

Buy the book here! >>>
support free software

12.33 CREATE DATABASE

Name

CREATE DATABASE -- create a new database

Synopsis

CREATE DATABASE name
    [ [ WITH ] [ OWNER [=] dbowner ]
           [ TEMPLATE [=] template ]
           [ ENCODING [=] encoding ]
           [ TABLESPACE [=] tablespace ]
           [ CONNECTION LIMIT [=] connlimit ] ]

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 USER.

Normally, the creator becomes the owner of the new database. Superusers can create databases owned by other users, by using the OWNER clause. They can even create databases owned by users with no special privileges. Non-superusers with CREATEDB privilege can only create databases owned by themselves.

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 may have been added to template1.

Parameters

name: The name of a database to create.
dbowner: The name of the database user who will own the new database, or DEFAULT to use the default (namely, the user executing the command).
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 Volume 3: Supported Character Sets.
tablespace: 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 for more information.
connlimit: How many concurrent connections can be made to this database. -1 (the default) means no limit.

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 is a wrapper program around this command, provided for convenience.

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 Volume 3: Template Databases for more information.

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.

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 which supports the ISO-8859-1 character set:

CREATE DATABASE music ENCODING 'LATIN1';

Compatibility

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