"Merlin Moncure" <[EMAIL PROTECTED]> writes: > Doing some testing on upcoming 8.1 devel and am having serious issues > with new bitmap index scan feature. It is easy to work around (just > disable it) but IMO the planner is using it when a regular index scan > should be strongly favored.
I think blaming the bitmap code is the wrong response. What I see in your example is that the planner doesn't know what the LIMIT value is, and accordingly is favoring a plan that isn't going to get blown out of the water if the LIMIT is large. I'd suggest not parameterizing the LIMIT. (But hmm ... I wonder if we could use estimate_expression_value for LIMIT items, instead of handling only simple Consts as the code does now?) regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster