On Tue, 2006-06-06 at 16:11, Tom Lane wrote: > Scott Marlowe <smarlowe@xxxxxxxxxxxxxxxxx> writes: > > The cost of not aborting on the first sort is that you may never see > > what the part of the plan is that's killing your query, since you never > > get the actual plan. > > Well, you can get the plan without waiting a long time; that's what > plain EXPLAIN is for. But I still disagree with the premise that you > can extrapolate anything very useful from an unfinished EXPLAIN ANALYZE > run. As an example, if the plan involves setup steps such as sorting or > loading a hashtable, cancelling after a minute might make it look like > the setup step is the big problem, distracting you from the possibility > that the *rest* of the plan would take weeks to run if you ever got to > it. Sure, but it would be nice to see it report the partial work. i.e. I got to using a nested loop, thought there would be 20 rows, processed 250,000 or so, timed out at 10 minutes, and gave up. I would find that useful.
