> For the complete documentation index, see [llms.txt](https://docs.postgresql.tw/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.postgresql.tw/internals/catalogs/catalog-pg-extension.md).
# 52.22. pg\_extension \#
The catalog `pg_extension` stores information about the installed extensions. See [Section 36.17](/server-programming/extend/extend-extensions.md) for details about extensions.
**Table 52.22. `pg_extension` Columns**
| Column Type
Description
|
| ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| oid oid
Row identifier
|
| extname name
Name of the extension
|
| extowner oid (references pg\_authid.oid)
Owner of the extension
|
| extnamespace oid (references 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\[] (references 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.
***
原文：[PostgreSQL 18.6 Documentation](https://www.postgresql.org/docs/18/catalog-pg-extension.html)（英文原文，待翻譯）
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