Which is fastest?
This:
SELECT id, title FROM questions LEFT JOIN users USING (userid) WHERE
zipcode = 2000;
or this:
SELECT id, title FROM questions WHERE userid IN (SELECT userid FROM
users WHERE zipcode = 2000);
I currently use the latter, but as subselects aren't ready yet I'm
currently selecting userids and then creating the select statement that
gets id and title.
Regards Jacob
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