> 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/ecpg/ecpg-sql-commands/ecpg-sql-deallocate-descriptor.md).

# DEALLOCATE DESCRIPTOR

### DEALLOCATE DESCRIPTOR

DEALLOCATE DESCRIPTOR — 釋放 SQL 描述區

### 語法

```

DEALLOCATE DESCRIPTOR name
```

### 說明

`DEALLOCATE DESCRIPTOR` 釋放具名 SQL 描述區。

### 參數

*`name`* [#](#ECPG-SQL-DEALLOCATE-DESCRIPTOR-NAME) : 即將釋放的描述區名稱。此名稱區分大小寫，可以是 SQL 識別字或主機變數。

### 範例

```

EXEC SQL DEALLOCATE DESCRIPTOR mydesc;
```

### 相容性

SQL 標準規定了 `DEALLOCATE DESCRIPTOR`。

### 另請參閱

[ALLOCATE DESCRIPTOR](/client-interfaces/ecpg/ecpg-sql-commands/ecpg-sql-allocate-descriptor.md), [GET DESCRIPTOR](/client-interfaces/ecpg/ecpg-sql-commands/ecpg-sql-get-descriptor.md), [SET DESCRIPTOR](/client-interfaces/ecpg/ecpg-sql-commands/ecpg-sql-set-descriptor.md)

***

原文：[PostgreSQL 18.6 Documentation](https://www.postgresql.org/docs/18/ecpg-sql-deallocate-descriptor.html)（英文原文，待翻譯）


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