The catalog pg_extension stores information about the installed extensions. See Section 35.15 for details about extensions.
Table 49-22. 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.
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