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OK, I made an, um, ah, assumption in my response. I assumed that "crt_date" is a field on vndmst and not item_master. If that is the case then this isn't a correlated subquery. Current_Date is a reserved value in SQL which holds, oddly enough, the current date. If it wasn't so then the subquery may or may not be correlated depending on where the current_Date value came from. As for the join, I agree that the result would be the same, but I'm not sure they would be executed the same. My first thought is that the original, with the IN clause would execute faster since it is a simpler query (or more appropriately two queries), however the outer query can't start until the inner query finishes. However in the case of the join query with query parallelism I believe you could get rows back faster. The answer to performance probably also depends on which release and PTF level you're on since IBM could, and should, change the optimizer as time goes on to get better and better. -Walden ------------ Walden H Leverich III President Tech Software (516) 627-3800 x11 (208) 692-3308 eFax WaldenL@TechSoftInc.com http://www.TechSoftInc.com
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