Tom Lane-2 wrote: > > It looks like it ought to be an O(N^2) > situation, so the improvement should be noticeable but not amazing. >
Hm, the performance was reasonable again when doing a cluster... So I believe this should be more a technical than an algorithmical/complexity issue. Maybe it is the way the hashtable is built and that order makes a difference in that case? In short: Why is clustered data not affected? Regards, panam -- View this message in context: http://postgresql.1045698.n5.nabble.com/Re-PERFORM-Hash-Anti-Join-performance-degradation-tp4443803p4445123.html Sent from the PostgreSQL - hackers mailing list archive at Nabble.com. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers