Actually, in your case it's probably the new optimisation regarding the use of IN (subquery). They're now optimised to the same lavel as EXISTS IIRC.
On Wed, Nov 12, 2003 at 05:46:23PM -0800, Reece Hart wrote: > On Wed, 2003-11-12 at 09:04, jake johnson wrote: > > > I also posted about the performance increase of 7.4, but I think that > > much of the difference you're seeing (because it's such a large > > difference) is probably due to the cleanliness of a newly restored > > database from backup. > > > I agree that this seems likely, except that the 7.3.4 database is > vacuumed nightly, and analyzed periodically. And about a week ago I > reclustered on the index intended to most facilitate this select. > Furthermore, merely hardcoding the subselect result achieves a > tremendous improvement (which was the workaround I used). So, I'm pretty > sure that it's not a vacuum, index use, or cleanliness issue. > > I also meant to add in my original post that the system is a dual 2.4G > xeon with 4GB of RAM. > > -Reece > > > > -- > Reece Hart, http://www.in-machina.com/~reece/, GPG:0x25EC91A0 0xD178AAF9 -- Martijn van Oosterhout <[EMAIL PROTECTED]> http://svana.org/kleptog/ > "All that is needed for the forces of evil to triumph is for enough good > men to do nothing." - Edmond Burke > "The penalty good people pay for not being interested in politics is to be > governed by people worse than themselves." - Plato
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