I second this...well third it really since Mark Murphy posted it earlier...


On Thu, Aug 13, 2015 at 2:10 PM, John Yeung <gallium.arsenide@xxxxxxxxx>

On Thu, Aug 13, 2015 at 1:35 PM, Stone, Joel <Joel.Stone@xxxxxxxxxx>
Yes there is a LF with a single primary unique key.

OK, that eliminates one possible problem. Darren brings up some more
"CQE vs. SQE" and "logical vs. index" issues. Assuming you have an
access path *that your query engine can use*, there should definitely
be a way to make the query run quickly.

One thing I noticed is that your query uses EXISTS. Now, I'm no SQL
expert, but EXISTS feels less "obviously optimizable" to me than IN,
especially since you have another WHERE inside your subselect. I would
have expressed your query as

select * from filePROD
where docid in
(select docid from fileFIX)

John Y.
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