On Tue, Jan 08, 2008 at 01:08:52AM +0100, Markus Schiltknecht wrote: > > Uh, which key are you talking about? AFAIU Simon's proposal, he suggests > maintaining min/max values for all columns of the table.
Right, but I think that's just because that approach is automatable. Only some use cases are going to be approproate to this. > Yeah, and if only *one* tuple in the 1G segment has: > > some_date <= '1998-12-31' OR some_date >= '2001-01-01' > > Segment Exclusion can't exclude that segment. That's all I'm saying. Correct. > Huh? I'm certainly not the one asking for it. Quite the opposite, I'm > warning from over-estimating the use of SE. Right; I think one should be clear that there are many -- maybe most -- uses of PostgreSQL where the proposal will be of no use. I just think we need to be clear that for the areas where it _can_ be useful, it could be very useful indeed. A ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq