Hi Folks, I'm new to Postgresql. I'm having great difficulties getting the performance I had hoped for from Postgresql 8.0. The typical query below takes ~20 minutes !! I hope an expert out there will tell me what I'm doing wrong - I hope *I* am doing something wrong. Hardware -------- Single processor, Intel Xeon 3.06 GHz machine running Red Hat Ent. 4. with 1.5 GB of RAM. The machine is dedicated to running Postgresql 8.0 and Apache/mod_perl etc. The database is being accessed for report generation via a web form. The web server talks to Pg over TCP/IP (I know, that I don't need to do this if they are all on the same machine, but I have good reasons for this and don't suspect that this is where my problems are - I have the same poor performance when running from psql on the server.) Database -------- Very simple, not fully normalized set of two tables. The first table, very small (2000 lines of 4 cols with very few chars and integers in in col). The other quite a bit larger (500000 lines with 15 cols. with the largest fields ~ 256 chars) Typical query ------------ SELECT n.name FROM node n WHERE n.name LIKE '56x%' AND n.type='H' AND n.usage='TEST' AND n.node_id NOT IN (select n.node_id FROM job_log j INNER JOIN node n ON j.node_id = n.node_id WHERE n.name LIKE '56x%' AND n.type='H' AND n.usage='TEST' AND j.job_name = 'COPY FILES' AND j.job_start >= '2005-11-14 00:00:00' AND (j.job_stop <= '2005-11-22 09:31:10' OR j.job_stop IS NULL)) ORDER BY n.name The node table is the small table and the job_log table is the large table. I've tried all the basic things that I found in the documentation like VACUUM ANALYZE, EXPLAIN etc., but I suspect there is something terribly wrong with what I'm doing and these measures will not shave off 19 min and 50 seconds off the query time. Any help and comments would be very much appreciated. Bealach
