Re: Highly obscure and erratic

On Wed, 19 Jun 2002, Varun Kacholia wrote:

> 1. SELECT * FROM dbmedia WHERE ID IN ((SELECT id FROM wdmedia WHERE
> word = 'whatever') )  LIMIT 20;

You probably didn't know this, but postgres is notorious for being
*very* bad at optimizing IN queries.  Try this instead:

SELECT * FROM dbmedia d WHERE EXISTS
  (SELECT 1 FROM wdmedia w WHERE w.id = d.id AND word = 'whatever')
 LIMIT 20;

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