On Fri, Jun 17, 2016 at 10:41 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: > While fixing the recent unpleasantness over parallel polymorphic > aggregates, I discovered that count_agg_clauses_walker's consideration > of an aggregate argument's typmod in estimating transition space > consumption has been broken since commit 34d26872e (which changed > Aggref.args from a simple expression list to a list of TargetEntry). > It had been looking at "exprTypmod((Node *) linitial(aggref->args))", > and nobody taught it that there was now a TargetEntry in the way that > it needed to look through to get a correct answer. > > Ordinarily I'd just summarily back-patch a fix, but that commit shipped > in 9.0, which means it's been broken a long time. I'm worried that > back-patching a change might be more likely to destabilize plan choices > than to do anything anybody's happy about. > > Thoughts?
I suspect the consequences here aren't too bad, or someone would have noticed by now. So I would be tempted to leave it alone in back-branches. But I might change my mind if it's actually awful... -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers