am Fri, dem 20.04.2007, um 12:59:01 +0100 mailte Richard Huxton folgendes: > A. Kretschmer wrote: > > > >It's not my problem - i found it in a forum (german) > >http://pg-forum.de/showthread.php?t=1332 > > > >If the list contains up to 195 entrys -> up to 195 bitmap index scans > >and BitmapOr -> 7.839ms > > > >If the list contains 196 entrys -> seq-scan -> 5591.567ms > > It looks like it's getting the row estimate badly wrong. > > "Seq Scan on t_datasets_searchindices_rel (cost=0.00..129053.50 > rows=159277 width=4) (actual time=0.213..5590.435 rows=325 loops=1)
Uh oh, i have overlook this. > > Probably worth increasing the statistics estimate for that column (ALTER > TABLE ... ALTER COLUMN ... SET STATISTICS=N) Thx for your hints! Andreas -- Andreas Kretschmer Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header) GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
