The pg_language system catalog table registers languages in which you can write functions or stored procedures. It is populated by CREATE LANGUAGE.
|lanname||name||Name of the language.|
|lanispl||boolean||This is false for internal languages (such as SQL) and true for user-defined languages. Currently, pg_dump still uses this to determine which languages need to be dumped, but this may be replaced by a different mechanism in the future.|
|lanpltrusted||boolean||True if this is a trusted language, which means that it is believed not to grant access to anything outside the normal SQL execution environment. Only superusers may create functions in untrusted languages.|
|lanplcallfoid||oid||pg_proc.oid||For noninternal languages this references the language handler, which is a special function that is responsible for executing all functions that are written in the particular language.|
|lanvalidator||oid||pg_proc.oid||This references a language validator function that is responsible for checking the syntax and validity of new functions when they are created. Zero if no validator is provided.|
|lanacl||aclitem||Access privileges for the language.|