In response to Lefteris : > Thank you all for your answers! > > Andrea, I see the other way around what you are saying: > > Sort (cost=7407754.12..7407754.13 rows=4 width=2) (actual > time=371188.821..371188.823 rows=7 loops=1) > Seq Scan on ontime (cost=0.00..7143875.40 rows=52775727 width=2) > (actual time=190938.959..346180.079 rows=52484047 loops=1) > > > I dont see the seq scan to ba a problem, and it is the correct choice > here because Year spans from 1999 to 2009 and the query asks from 2000 > and on, so PG correctly decides to use seq scan and not index access. Thats right. But this is not a contradiction, this seq-scan *is* the real problem, not the sort. And yes, as others said, increment the work_mem isn't the solution. It is counterproductive, because you lost buffer-cache. Andreas, note the 's' at the end ;-) -- Andreas Kretschmer Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header) GnuPG: 0x31720C99, 1006 CCB4 A326 1D42 6431 2EB0 389D 1DC2 3172 0C99 -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
