一个带更新触发器表为啥不能批量更新,我应该怎么做?

[13501384036]

我有一个
主表A:
ID FLAG
----------------
1 0
2 0
3 0

副表B:
ID Flag
--------------
1 0
2 0
3 0

在主表上有一个触发如下:

CREATE TRIGGER TR_Update_A ON dbo.A
FOR update
AS
declare @a int
declare @b int
set @a = (select Flag from inserted)
set @b = (select id from inserted)
if @a = 9
begin
update JFInfoTab set Flag = 1 where ID = @b
end


问题:
当我在用这样的SQL语句更新主表时,发生错误,请问为啥?在不改变SQL语句的情况下该如何解决?
Update A set Flag = 1 where Flag = 0

[zjcxc]

CREATE TRIGGER TR_Update_A ON dbo.A
FOR update
AS
/*
declare @a int
declare @b int
set @a = (select Flag from inserted)
set @b = (select id from inserted)
if @a = 9
begin
update JFInfoTab set Flag = 1 where ID = @b
end
*/
if update(flag)
update JFInfoTab set flag=1
from JFInfoTab a join inserted b on a.id=b.id