createlang [connection-options...] [langname] dbname
createlang [connection-options...] --list | -l dbname
createlang accepts the following command line arguments:
Specifies the name of the backend programming language to be defined. createlang will prompt for langname if it is not specified on the command line.
Specifies which database the language should be added.
Shows a list of already installed languages in the target database (which must be specified).
createlang also accepts the following command line arguments for connection parameters:
Specifies the hostname of the machine on which the postmaster is running. If host begins with a slash, it is used as the directory for the unix domain socket.
Specifies the Internet TCP/IP port or local Unix domain socket file extension on which the postmaster is listening for connections.
Username to connect as.
Force password prompt.
Most error messages are self-explanatory. If not, run createlang with the --echo option and see under the respective SQL command for details. Check also under psql for more possibilities.
createlang is a utility for adding a new programming language to a Postgres database. createlang currently accepts several languages, plpgsql, pltcl, pltclu, and plperl.
Although backend programming languages can be added directly using several SQL commands, it is recommended to use createlang because it performs a number of checks and is much easier to use. See CREATE LANGUAGE for more.