> 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/15/client-interfaces/the-information-schema/36.21.-domain_udt_usage.md).

# 37.22. domain\_udt\_usage

## 37.22. domain\_udt\_usage

The view `domain_udt_usage` identifies all domains that are based on data types owned by a currently enabled role. Note that in PostgreSQL, built-in data types behave like user-defined types, so they are included here as well.

**Table 37.20. `domain_udt_usage` Columns**

| <p>Column Type</p><p>Description</p>                                                                                                                           |
| -------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| <p><code>udt\_catalog</code> <code>sql\_identifier</code></p><p>Name of the database that the domain data type is defined in (always the current database)</p> |
| <p><code>udt\_schema</code> <code>sql\_identifier</code></p><p>Name of the schema that the domain data type is defined in</p>                                  |
| <p><code>udt\_name</code> <code>sql\_identifier</code></p><p>Name of the domain data type</p>                                                                  |
| <p><code>domain\_catalog</code> <code>sql\_identifier</code></p><p>Name of the database that contains the domain (always the current database)</p>             |
| <p><code>domain\_schema</code> <code>sql\_identifier</code></p><p>Name of the schema that contains the domain</p>                                              |
| <p><code>domain\_name</code> <code>sql\_identifier</code></p><p>Name of the domain</p>                                                                         |

***

原文：[PostgreSQL 15.19 Documentation](/15/client-interfaces/the-information-schema/36.21.-domain_udt_usage.md)（英文原文，待翻譯）


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