Re: Very slow queries w/ NOT IN preparation (seems like a bug, test case) - Mailing list pgsql-general

>> What configure options did you use, what locale/encoding are you using,
>> what nondefault settings have you got in postgresql.conf?
>>
>>                        regards, tom lane
>
> You are right. I've found the odd thing (that completely drives me
> mad) in postgresql.conf.
>
> You are able to reproduce slow-not-in queries by switching
> constraint_exclusion to on in your postgresql.conf and running my test
> (which is attached to the first message).
>

On more thing:

If you do

EXPLAIN SELECT 1 FROM table1 WHERE table1_id NOT IN (SELECT column1
FROM (VALUES (123),(456),(789),... a lot of IDs here...)_);

it works as fast as with constraint_exclusion turned to off.

--
Regards,
Sergey Konoplev
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