Practical PostgreSQL

Adding PL/pgSQL to Your Database

Programming languages are made available to databases by being created as a database object. You will therefore need to add the PL/pgSQL language to your database before you can use it (it is installed with PostgreSQL by default). The following steps demonstrate how to add PL/pgSQL to an existing database.

Adding PL/pgSQL to Your Database

To add PL/pgSQL to your PostgreSQL database, you can either use the createlang application from the command line, or the CREATE LANGUAGE SQL command from within a database client such as psql. The use of the CREATE LANGUAGE command first requires the creation of the PL/pgSQL call handler, which is the function that actually processes and interprets the PL/pgSQL code.

Though the createlang utility is simpler to use, as it abstracts the creation of the call handler and the language away from the user, the following sections document both methods.

Note

Installing PL/pgSQL in the template1 database causes all subsequent databases that are created with template1 as their template (which is the default) to also have PL/pgSQL installed.

Using psql to add PL/pgSQL

CREATE LANGUAGE is the SQL command which adds procedural languages to the currently connected database. Before it can be used, however, the CREATE FUNCTION command must first be used to create the procedural call handler.

Here is the syntax to create a PL/pgSQL call handler ...