获取更新的行

Question

我有一个更新一条记录的查询,只有一条记录.是否有方法可以在同一查询中更新Id,例如插入时选择ScopeIdentity.

UPDATE Task
SET MyTime = GetDate(), MyUserId = @userid
FROM (select top 1 table where SomeStuff)

Select Lastrow that just got updated.

Answer 1

根据您在做什么，您可能需要使用OUTPUT. 一种可能性是指定一个临时表/表变量。

DECLARE @T TABLE
(
    MyID INT NOT NULL
)

UPDATE Task
SET MyTime = GetDate(), MyUserId = @userid
OUTPUT INSERTED.MyID INTO @T
FROM (/* your FROM clause here */) Task

gbn 在我之前得到了一个编辑，基本上和上面说的一样。我想补充一点，另一种方法是先获取 ID，然后按 ID 更新。此外，TOP 1 应该几乎总是与ORDER BY.

-- You may need to clean up the error handling. I just wanted
-- to put something simple in to remind that it is necessary.
DECLARE @userid INT; SET @userid = /* e.g., */ 1234
BEGIN TRANSACTION
IF @@ERROR <> 0 RETURN
DECLARE @TaskID INT
SET @TaskID = (SELECT TOP 1 TaskID FROM Task WITH (UPDLOCK) ORDER BY /* e.g., */ TaskID) -- TaskID should be the PK of MyTable. Must be unique.
IF @@ERROR <> 0 BEGIN ROLLBACK TRANSACTION RETURN END
UPDATE Task
SET MyTime = GETDATE(), MyUserId = @userid
WHERE TaskID = @TaskID
COMMIT TRANSACTION

Answer 2

是的,使用OUTPUT子句

例:

UPDATE Task
SET MyTime = GetDate(), MyUserId = @userid
OUTPUT INSERTED.MyID
FROM (select top 1 table where SomeStuff)

要么

DECLARE @MyTableVar TABLE (...

...
UPDATE Task
SET MyTime = GetDate(), MyUserId = @userid
OUTPUT INSERTED.MyID INTO @MyTableVar 
FROM (select top 1 table where SomeStuff)