> 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-shdescription.md).

# 52.49. pg\_shdescription \#

The catalog `pg_shdescription` stores optional descriptions (comments) for shared database objects. Descriptions can be manipulated with the [`COMMENT`](/reference/sql-commands/sql-comment.md) command and viewed with psql's `\d` commands.

See also [`pg_description`](/internals/catalogs/catalog-pg-description.md), which performs a similar function for descriptions involving objects within a single database.

Unlike most system catalogs, `pg_shdescription` is shared across all databases of a cluster: there is only one copy of `pg_shdescription` per cluster, not one per database.

**Table 52.49. `pg_shdescription` 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="/pages/b1fii6hWVNacZFXaxWON"><code>pg\_class</code></a>.<code>oid</code>)</p><p>The OID of the system catalog this object appears in</p> |
| <p><code>description</code> <code>text</code></p><p>Arbitrary text that serves as the description of this object</p>                                                                                    |

<br>

***

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


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