Off hanbd I can't recommend anything, bur perhaps you could post the details of the tables (columns, indexes),and some info on what version of postgres you are using.
Are the tables recently analyzed ? How many rows in them ? Greg Williamson DBA GlobeXplorer LLC -----Original Message----- From: [EMAIL PROTECTED] on behalf of Ruben Rubio Sent: Tue 10/17/2006 2:05 AM To: pgsql-performance@postgresql.org Cc: Subject: [PERFORM] Optimization of this SQL sentence -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 This SQL sentence is very simple. I need to get better results. I have tried some posibilities and I didn't get good results. SELECT max(idcomment) FROM ficha vf INNER JOIN comment c ON (vf.idficha=c.idfile AND (idestado=3 OR idestado=4)) WHERE idstatus=3 AND ctype=1 QUERY PLAN Aggregate (cost=2730.75..2730.76 rows=1 width=4) (actual time=188.463..188.469 rows=1 loops=1) -> Hash Join (cost=1403.44..2730.72 rows=11 width=4) (actual time=141.464..185.404 rows=513 loops=1) Hash Cond: ("outer".idfile = "inner".idficha) -> Seq Scan on "comment" c (cost=0.00..1321.75 rows=1083 width=8) (actual time=0.291..36.112 rows=642 loops=1) Filter: ((idstatus = 3) AND (ctype = 1)) -> Hash (cost=1403.00..1403.00 rows=178 width=4) (actual time=141.004..141.004 rows=6282 loops=1) -> Seq Scan on ficha vf (cost=0.00..1403.00 rows=178 width=4) (actual time=0.071..97.885 rows=6282 loops=1) Filter: (((idestado)::text = '3'::text) OR ((idestado)::text = '4'::text)) Total runtime: 188.809 ms Thanks in advance, Ruben Rubio -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2.2 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD4DBQFFNJzfIo1XmbAXRboRAgPRAJ99+S9wL21b+JN14bQbAoREFXYUcQCYpfEZ p1MCcDMWqTxzSdtssUFWOw== =rUHB -----END PGP SIGNATURE----- ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq ------------------------------------------------------- Click link below if it is SPAM [EMAIL PROTECTED] "https://mailscanner.globexplorer.com/dspam/dspam.cgi?signatureID=45349c86275246672479766&[EMAIL PROTECTED]&retrain=spam&template=history&history_page=1" !DSPAM:45349c86275246672479766! ------------------------------------------------------- ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match