> 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-describe.md).

# DESCRIBE

### DESCRIBE

DESCRIBE — 取得備妥陳述式或結果集的資訊

### 語法

```

DESCRIBE [ OUTPUT ] prepared_name USING [ SQL ] DESCRIPTOR descriptor_name
DESCRIBE [ OUTPUT ] prepared_name INTO [ SQL ] DESCRIPTOR descriptor_name
DESCRIBE [ OUTPUT ] prepared_name INTO sqlda_name
```

### 說明

`DESCRIBE` 取得備妥陳述式所含結果欄位的中繼資料資訊，而不會實際擷取資料列。

### 參數

*`prepared_name`* [#](#ECPG-SQL-DESCRIBE-PREPARED-NAME) : 備妥陳述式的名稱。可以是 SQL 識別字或主機變數。

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

*`sqlda_name`* [#](#ECPG-SQL-DESCRIBE-SQLDA-NAME) : SQLDA 變數名稱。

### 範例

```

EXEC SQL ALLOCATE DESCRIPTOR mydesc;
EXEC SQL PREPARE stmt1 FROM :sql_stmt;
EXEC SQL DESCRIBE stmt1 INTO SQL DESCRIPTOR mydesc;
EXEC SQL GET DESCRIPTOR mydesc VALUE 1 :charvar = NAME;
EXEC SQL DEALLOCATE DESCRIPTOR mydesc;
```

### 相容性

SQL 標準規定了 `DESCRIBE`。

### 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)

***

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


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