The catalog pg_extension stores information about the installed extensions. See Section 35.15 for details about extensions.

Table 49-22. pg_extension Columns

Name Type References Description
oid oid Row identifier (hidden attribute; must be explicitly selected)
extname name Name of the extension
extowner oid pg_authid .oid Owner of the extension
extnamespace oid pg_namespace .oid Schema containing the extension's exported objects
extrelocatable bool True if extension can be relocated to another schema
extversion text Version name for the extension
extconfig oid[] pg_class .oid Array of regclass OIDs for the extension's configuration table(s), or NULL if none
extcondition text[] Array of WHERE -clause filter conditions for the extension's configuration table(s), or NULL if none

Note that unlike most catalogs with a "namespace" column, extnamespace is not meant to imply that the extension belongs to that schema. Extension names are never schema-qualified. Rather, extnamespace indicates the schema that contains most or all of the extension's objects. If extrelocatable is true, then this schema must in fact contain all schema-qualifiable objects belonging to the extension.