createdb

createdb
Prev	Up	PostgreSQL Client Applications	Home	Next

Description

createdb creates a new PostgreSQL database.

Normally, the database user who executes this command becomes the owner of the new database. However, a different owner can be specified via the -O option, if the executing user has appropriate privileges.

createdb is a wrapper around the SQL command CREATE DATABASE. There is no effective difference between creating databases via this utility and via other methods for accessing the server.

Options

createdb accepts the following command-line arguments:

dbname: Specifies the name of the database to be created. The name must be unique among all PostgreSQL databases in this cluster. The default is to create a database with the same name as the current system user.
description: Specifies a comment to be associated with the newly created database.
-D tablespace --tablespace=tablespace: Specifies the default tablespace for the database. (This name is processed as a double-quoted identifier.)
-e --echo: Echo the commands that createdb generates and sends to the server.
-E encoding --encoding=encoding: Specifies the character encoding scheme to be used in this database. The character sets supported by the PostgreSQL server are described in Section 23.3.1.
-l locale --locale=locale: Specifies the locale to be used in this database. This is equivalent to specifying both --lc-collate and --lc-ctype.
--lc-collate=locale: Specifies the LC_COLLATE setting to be used in this database.
--lc-ctype=locale: Specifies the LC_CTYPE setting to be used in this database.
-O owner --owner=owner: Specifies the database user who will own the new database. (This name is processed as a double-quoted identifier.)
-T template --template=template: Specifies the template database from which to build this database. (This name is processed as a double-quoted identifier.)
-V --version: Print the createdb version and exit.
-? --help: Show help about createdb command line arguments, and exit.

The options -D, -l, -E, -O, and -T correspond to options of the underlying SQL command CREATE DATABASE; see there for more information about them.

createdb also accepts the following command-line arguments for connection parameters:

-h host --host=host

Specifies the host name of the machine on which the server is running. If the value begins with a slash, it is used as the directory for the Unix domain socket.

-p port --port=port

Specifies the TCP port or the local Unix domain socket file extension on which the server is listening for connections.

-U username --username=username

User name to connect as.

-w --no-password

Never issue a password prompt. If the server requires password authentication and a password is not available by other means such as a .pgpass file, the connection attempt will fail. This option can be useful in batch jobs and scripts where no user is present to enter a password.

-W --password

Force createdb to prompt for a password before connecting to a database.

This option is never essential, since createdb will automatically prompt for a password if the server demands password authentication. However, createdb will waste a connection attempt finding out that the server wants a password. In some cases it is worth typing -W to avoid the extra connection attempt.

--maintenance-db=dbname

Specifies the name of the database to connect to when creating the new database. If not specified, the postgres database will be used; if that does not exist (or if it is the name of the new database being created), template1 will be used. This can be a connection string. If so, connection string parameters will override any conflicting command line options.

Environment

PGDATABASE: If set, the name of the database to create, unless overridden on the command line.
PGHOST PGPORT PGUSER: Default connection parameters. PGUSER also determines the name of the database to create, if it is not specified on the command line or by PGDATABASE.
PG_COLOR: Specifies whether to use color in diagnostic messages. Possible values are always, auto and never.

This utility, like most other PostgreSQL utilities, also uses the environment variables supported by libpq (see Section 33.14).

Diagnostics

In case of difficulty, see CREATE DATABASE and psql for discussions of potential problems and error messages. The database server must be running at the targeted host. Also, any default connection settings and environment variables used by the libpq front-end library will apply.

Examples

To create the database demo using the default database server:

$ createdb demo

To create the database demo using the server on host eden, port 5000, using the template0 template database, here is the command-line command and the underlying SQL command:

$ createdb -p 5000 -h eden -T template0 -e demo
CREATE DATABASE demo TEMPLATE template0;