Am I going about this the right way? I want to find pairs of entities
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?

Kerry

Try 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