pg_pltemplate stores “template” information for procedural languages. A template for a language allows the language to be created in a particular database by a simple
CREATE LANGUAGE command, with no need to specify implementation details.
Unlike most system catalogs,
pg_pltemplate is shared across all databases of a cluster: there is only one copy of
pg_pltemplate per cluster, not one per database. This allows the information to be accessible in each database as it is needed.
|Name of the language this template is for|
|True if language is considered trusted|
|True if language may be created by a database owner|
|Name of call handler function|
|Name of anonymous-block handler function, or null if none|
|Name of validator function, or null if none|
|Path of shared library that implements language|
|Access privileges for template (not actually used)|
There are not currently any commands that manipulate procedural language templates; to change the built-in information, a superuser must modify the table using ordinary
It is likely that
pg_pltemplate will be removed in some future release of PostgreSQL, in favor of keeping this knowledge about procedural languages in their respective extension installation scripts.