I don't think that is correct. It seems to do the subselect (return
a set of rows) and THEN join the result to the outer select. A few
responses have stated what you said - that EXISTS simply returns TRUE
or FALSE. But I think that it must do this for each row in the outer
select in the case where a join is occurring?
Maybe I am wrong, I don't know SQL and it is elusive and powerful and
complex so I don't understand all the subtleties.
Dan Kimmel on Thursday, December 06, 2012 11:01 AM wrote:
The EXISTS says "are there any". You get the same results in the
outer select whether there's one or many results from the
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