in a table that have some relationship (such as a field being the
same), so I
select t1.id, t2.id from sametable t1 join sametable t2 on
t1.id<>t2.id
where t1.fieldx=t2.fieldx ...
The trouble is, this returns each pair twice, e.g.
B C
C B
M N
N M
Is there a way to do this kind of thing and only get each pair once?
KerryTry this:
SELECT t1.id, t2.id
FROM sametable t1
JOIN sametable t2
ON t1.id < t2.id
WHERE t1.fieldx=t2.fieldx ...
(a subtle difference in the ON clause)
--
David Portas
----
Please reply only to the newsgroup
--|||Many thanks for the tip. Very elegant. Makes the join half as big too!
Thanks,
Kerry
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