Hi All,Here is my scenario.I have two tables T1 (Sid int not null, Pid int not null) & T2(Sid int, Pid int). T1 has composite primary key on (sid, pid)... Now I want to insert data from T2 to T1 making sure the data I am inserting in T1 does not exists there... Ofcourse If it exists it will fails due to composite primary key violation. However I don't want it to fail. I want to make sure before hand only when I insert data.So basically, I want to check that the data in T2 table doesn't exist in T1 table first and if not then only insert it in table T1. OR insert only that data which doesn't exist in T1.Thanks in advance for the help.