> 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/client-interfaces/information-schema/infoschema-domain-udt-usage.md).

# 35.22. domain\_udt\_usage \#

檢視表 `domain_udt_usage` 列出以目前已啟用角色所擁有資料型別為基礎的所有 domain。請注意，在 PostgreSQL 中，內建資料型別的行為如同使用者定義型別，因此 也包含在此處。

**表 35.20. `domain_udt_usage` 欄位**

| <p>欄位類型</p><p>說明</p>                                                                               |
| -------------------------------------------------------------------------------------------------- |
| <p><code>udt\_catalog</code> <code>sql\_identifier</code></p><p>定義 domain 資料型別的資料庫名稱（一律為目前資料庫）</p> |
| <p><code>udt\_schema</code> <code>sql\_identifier</code></p><p>定義 domain 資料型別的 schema 名稱</p>       |
| <p><code>udt\_name</code> <code>sql\_identifier</code></p><p>domain 資料型別名稱</p>                     |
| <p><code>domain\_catalog</code> <code>sql\_identifier</code></p><p>包含 domain 的資料庫名稱（一律為目前資料庫）</p>  |
| <p><code>domain\_schema</code> <code>sql\_identifier</code></p><p>包含 domain 的 schema 名稱</p>        |
| <p><code>domain\_name</code> <code>sql\_identifier</code></p><p>domain 名稱</p>                      |

<br>

***

【[PostgreSQL 18.6 文件](https://www.postgresql.org/docs/18/infoschema-domain-udt-usage.html)】


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