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SQL code:
1¡¢@@ERROR

2¡¢isnull()


SQL code:
if exists(select 1 from tb where ) --ÅжÏÊÇ·ñ´æÔÚÄãÒª²éÕҵļǼ Èç¹û´æÔÚÔòupdate
update tb set col=''
else
insert tb values() --Èç¹û²»´æÔÚÔò²åÈë


SQL code:
CREATE PROC P(@ID INT,@NAME VARCHAR(10))
AS
IF NOT EXISTS(SELECT * from TB T WHERE ID=@ID AND NAME=@NAME)
INSERT TB (ID,NAME)SELECT @ID,@NAME
ELSE
UPDATE TB SET ID=@ID ,NAME=@NAME WHERE Ìõ¼þ
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SQL code:
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CREATE TRIGGER TRI ON TB
INSTEAD OF INSERT
AS
IF NOT EXISTS(SELECT * from TB T WHERE EXISTS(SELECT


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2009-1-1 13:00:01 12345
2009-1-1 13:00:02 12345
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