The catalog pg_extension stores information about the installed extensions. See Section 36.15 for details about extensions.
Table 50-22. pg_extension Columns
|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.
If you see anything in the documentation that is not correct, does not match your experience with the particular feature or requires further clarification, please use this form to report a documentation issue.