> 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-set-connection.md).

# SET CONNECTION

### SET CONNECTION

SET CONNECTION — 選取資料庫連線

### 語法

```

SET CONNECTION [ TO | = ] connection_name
```

### 說明

`SET CONNECTION` 設定「目前」資料庫連線；除非另有指定，所有命令都使用此連線。

### 參數

*`connection_name`* [#](#ECPG-SQL-SET-CONNECTION-CONNECTION-NAME) : 由 `CONNECT` 命令建立的資料庫連線名稱。

`CURRENT` [#](#ECPG-SQL-SET-CONNECTION-CURRENT) : 將連線設為目前連線（因此不會發生任何變化）。

### 範例

```

EXEC SQL SET CONNECTION TO con2;
EXEC SQL SET CONNECTION = con1;
```

### 相容性

SQL 標準規定了 `SET CONNECTION`。

### 另請參閱

[CONNECT](/client-interfaces/ecpg/ecpg-sql-commands/ecpg-sql-connect.md), [DISCONNECT](/client-interfaces/ecpg/ecpg-sql-commands/ecpg-sql-disconnect.md)

***

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


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