Alternative to NOT EXISTS
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by Dave Colwell
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Published on 2010-04-30T05:04:41Z
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2010/04/30
5:07 UTC
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Hi all,
I have two tables linked by an ID column, lets call them Table A and table B. My goal is to find all the records in table A that have no record in table B. For instance:
Table A:
ID----Value
1-----value1
2-----value2
3-----value3
4-----value4
Table B
ID----Value
1-----x
2-----y
4-----z
4-----l
As you can see, record with ID = 3 does not exist in table B, so i want a query that will give me record 3 from table A. the way i am currently doing this is by saying AND NOT EXISTS (SELECT ID FROM TableB)
but since the tables are huge, the performance on this is terrible. Also, when i tried using a Left Join where TableB.ID is null, it didnt work. Can anyone suggest an alternative?
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