Neil Conway <[EMAIL PROTECTED]> writes: > Tom Lane wrote: >> This is something we need to consider, but we'll need more evidence >> before making a choice. One thing that we have very little data about >> is how much difference it makes in the quality of planner choices.
> Right, but is there a practical way to actually get this data? I haven't thought of one yet, but perhaps someone will have an idea. >> Also, I would expect that larger stats targets would slow down the parts >> of the planner that look at the stats, since there are more data values >> to examine. I do not have any numbers about this cost though --- do you >> want to try to get some? > Given the magnitude of the change (25 data elements versus 10), I > wouldn't expect this to produce a major change in the total runtime of > the optimizer. I wouldn't either, but if we need to raise the stats target to 100 or 1000 to make a meaningful difference, then the question becomes more urgent. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 7: don't forget to increase your free space map settings