Eric Raskin <eraskin@xxxxxxxxxxxx> writes: > And, of course, your explanation that inserts will not be parallelized must > be the reason. I will certainly re-vacuum the tables. I wonder why > auto-vacuum didn't collect better stats. vacuum analyze <table> is all I > need, right? Plain ANALYZE is enough to collect stats; but I doubt that'll improve matters for you. The problem is basically that the planner can't do anything with a CASE construct, so you end up with default selectivity estimates for anything involving a CASE, statistics or no statistics. You need to try to reformulate the query with simpler join conditions. > As a last resort, what about a PL/PGSQL procedure loop on the query > result? Since the insert is very few rows relative to the work the select > has to do, I could just turn the insert.. select.. into a for loop. Then > the select could be parallel? Maybe, but you're still skating on a cliff edge. I think it's pure chance that the parallelized query is working acceptably well; next month with slightly different conditions, it might not. regards, tom lane
