> 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/views/view-pg-available-extension-versions.md).

# 53.4. pg\_available\_extension\_versions \#

The `pg_available_extension_versions` view lists the specific extension versions that are available for installation. See also the [`pg_extension`](/internals/catalogs/catalog-pg-extension.md) catalog, which shows the extensions currently installed.

**Table 53.4. `pg_available_extension_versions` Columns**

| <p>Column Type</p><p>Description</p>                                                                                                                                    |
| ----------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| <p><code>name</code> <code>name</code></p><p>Extension name</p>                                                                                                         |
| <p><code>version</code> <code>text</code></p><p>Version name</p>                                                                                                        |
| <p><code>installed</code> <code>bool</code></p><p>True if this version of this extension is currently installed</p>                                                     |
| <p><code>superuser</code> <code>bool</code></p><p>True if only superusers are allowed to install this extension (but see <code>trusted</code>)</p>                      |
| <p><code>trusted</code> <code>bool</code></p><p>True if the extension can be installed by non-superusers with appropriate privileges</p>                                |
| <p><code>relocatable</code> <code>bool</code></p><p>True if extension can be relocated to another schema</p>                                                            |
| <p><code>schema</code> <code>name</code></p><p>Name of the schema that the extension must be installed into, or <code>NULL</code> if partially or fully relocatable</p> |
| <p><code>requires</code> <code>name\[]</code></p><p>Names of prerequisite extensions, or <code>NULL</code> if none</p>                                                  |
| <p><code>comment</code> <code>text</code></p><p>Comment string from the extension's control file</p>                                                                    |

<br>

The `pg_available_extension_versions` view is read-only.

***

原文：[PostgreSQL 18.6 Documentation](https://www.postgresql.org/docs/18/view-pg-available-extension-versions.html)（英文原文，待翻譯）


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