On Thu, 21 Nov 2002, Christopher Kings-Lynne wrote: > > > I think his point is that they _should_ be equivalent. Surely there's > > > something in the optimiser that discards '=true' stuff, like 'a=a' > should be > > > discarded? > > > > I figure that's what he meant, but it isn't what was said. ;) > > > > "col" isn't of the general form "indexkey op constant" or "constant op > > indexkey" which I presume it's looking for given the comments in > > indxpath.c. I'm not sure what the best way to make it work would be given > > that presumably we'd want to make col IS TRUE/FALSE use an index at the > > same time (since that appears to not do so as well). > > Not that I see the point of indexing booleans, but hey :)
While full indexes do seem futile, partial indexes can be quite useful. select articles from forum where approved is false if 99.9% of all articles are approved would be quite common. ---------------------------(end of broadcast)--------------------------- TIP 6: Have you searched our list archives? http://archives.postgresql.org
