> 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-allocate-descriptor.md).

# ALLOCATE DESCRIPTOR

### ALLOCATE DESCRIPTOR

ALLOCATE DESCRIPTOR — 配置 SQL 描述區

### 語法

```

ALLOCATE DESCRIPTOR name
```

### 說明

`ALLOCATE DESCRIPTOR` 配置新的具名 SQL 描述區，可用於 PostgreSQL 伺服器與主機程式之間交換資料。

使用完畢後，應使用 `DEALLOCATE DESCRIPTOR` 命令釋放描述區。

### 參數

*`name`* [#](#ECPG-SQL-ALLOCATE-DESCRIPTOR-NAME) : SQL 描述區名稱，區分大小寫。可以是 SQL 識別字或主機變數。

### 範例

```

EXEC SQL ALLOCATE DESCRIPTOR mydesc;
```

### 相容性

SQL 標準規定了 `ALLOCATE DESCRIPTOR`。

### 另請參閱

[DEALLOCATE DESCRIPTOR](/client-interfaces/ecpg/ecpg-sql-commands/ecpg-sql-deallocate-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-allocate-descriptor.html)（英文原文，待翻譯）


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