On Tue, Dec 30, 2008 at 1:59 PM, bricklen <bricklen@xxxxxxxxx> wrote: > Hi, I am re-posting my question here after trying to find a solution > in the PHP pgsql list with no luck. > > I am experiencing some performance issues that I think are stemming > from prepared statements. I have a pretty simple query: > -- bad plan, from prepared statement > -- > dev=# prepare fooplan (date,date,int,int) as > dev-# SELECT cl.idOffer AS campaign, cl.idAffiliate AS affiliate, > cl.idCreative AS creative, cl.subid, cl.datetime > dev-# FROM click AS cl LEFT JOIN conversion AS co ON cl.clickGenerated > = co.clickGenerated > dev-# WHERE cl."date" >= $1 > dev-# AND cl."date" <= $2 > dev-# AND cl.idAffiliate = $3 > dev-# LIMIT $4; Your problem is that the query as written is hard to plan. The database has no idea what you pass in, it has to guess. (IMO, It almost always guesses wrong...I think it should assume 1 row returned). Also, the db has no idea what you want to pass in at plan time for date. what indexes do you have on click? merlin -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
