---
title: "pg_extension"
id: catalog-pg-extension
pg_version: "20devel"
---

<a id="catalog-pg-extension"></a>

## 52.22. pg_extension

The catalog pg_extension stores information about the installed extensions. See [Section 36.17](extend-extensions.md) for details about extensions. 

**pg_extension Columns**

| Column Type | Description | 
| --- | --- |
| `oid` `oid` | Row identifier |
| `extname` `name` | Name of the extension |
| `extowner` `oid` (references [pg_authid](catalog-pg-authid.md).`oid`) | Owner of the extension |
| `extnamespace` `oid` (references [pg_namespace](catalog-pg-namespace.md).`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[]` (references [pg_class](catalog-pg-class.md).`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.