On Wed, Nov 28, 2007 at 09:16:08PM +0100, cluster wrote: > Hmm, actually I still don't understand why it takes 6400 ms to fetch the > rows. As far as I can see the index used is "covering" so that real row > lookups shouldn't be necessary. The indexes don't contain visibility information, so Postgres has to look up the row on disk to verify it isn't dead. > Also, only the the random_numbers induces by questions with status = 1 > should be considered - and this part is a relatively small subset. Again, you'll need to have a combined index if you want this to help you any. /* Steinar */ -- Homepage: http://www.sesse.net/ ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
