TSQL MERGE命令似乎並未實際合併

Question

我正在研究代碼here。

當我下面的代碼從那裏砍正貼：

- 用正確指定的連接條件MERGE語句。

USE tempdb; 
GO 
BEGIN TRAN; 
MERGE Target AS T 
USING Source AS S 
ON (T.EmployeeID = S.EmployeeID) 
WHEN NOT MATCHED BY TARGET AND S.EmployeeName LIKE 'S%' 
    THEN INSERT(EmployeeID, EmployeeName) VALUES(S.EmployeeID, S.EmployeeName) 
WHEN MATCHED 
    THEN UPDATE SET T.EmployeeName = S.EmployeeName 
WHEN NOT MATCHED BY SOURCE AND T.EmployeeName LIKE 'S%' 
    THEN DELETE 
OUTPUT $action, inserted.*, deleted.*; 
ROLLBACK TRAN; 
GO 

它產生他們說的輸出，但它實際上並沒有改變TARGET表。我如何才能真正改變TARGET表的結果？是否有某種開關？

Answer 1

與COMMIT TRAN;

更換ROLLBACK TRAN;目標表被改變，因此，你看到的是正確OUTPUT但隨後你被回滾事務撤銷其在未來的聲明。