> 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/internals/system-catalogs/pg_description.md).

# 53.19. pg\_description

## 53.19. pg\_description

The catalog `pg_description` stores optional descriptions (comments) for each database object. Descriptions can be manipulated with the [`COMMENT`](/15/reference/sql-commands/comment.md) command and viewed with psql's `\d` commands. Descriptions of many built-in system objects are provided in the initial contents of `pg_description`.

See also [`pg_shdescription`](/15/internals/system-catalogs/pg_shdescription.md), which performs a similar function for descriptions involving objects that are shared across a database cluster.

**Table 53.19. `pg_description` Columns**

| <p>Column Type</p><p>Description</p>                                                                                                                                                                                                            |
| ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| <p><code>objoid</code> <code>oid</code> (references any OID column)</p><p>The OID of the object this description pertains to</p>                                                                                                                |
| <p><code>classoid</code> <code>oid</code> (references <a href="/15/internals/system-catalogs/pg_class.md"><code>pg\_class</code></a>.<code>oid</code>)</p><p>The OID of the system catalog this object appears in</p>                           |
| <p><code>objsubid</code> <code>int4</code></p><p>For a comment on a table column, this is the column number (the <code>objoid</code> and <code>classoid</code> refer to the table itself). For all other object types, this column is zero.</p> |
| <p><code>description</code> <code>text</code></p><p>Arbitrary text that serves as the description of this object</p>                                                                                                                            |

***

原文：[PostgreSQL 15.19 Documentation](/15/internals/system-catalogs/pg_description.md)（英文原文，待翻譯）


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