Re: [SQL] performance problems of a complex query with 2 subselects
pierre@desertmoon.com
From: pierre@desertmoon.com
To: juris@rfb.lv (Juris)
Cc: pgsql-sql@postgreSQL.org
Date: 1999-02-05T16:22:58Z
Lists: pgsql-sql
> > Hello! > > I am quite new to PostgreSQL and was hoping to use it as an alternative > to MS Access for the product catalog software I am developing (the data > is represented in a meta-model). > > I fully recreated the environment I had on MS Access (see attachment) > and tried to run the query. > > The execution time for this query on MS Access for 40000 records was > approx. 10 seconds. > First the pgsql query on 400 records just seemed to hang. I installed a > newer version of pgsql (6.4.2), created indices on the columns > used until 'explain' showed only 1 'seq search' (couldn't get rid of > that one). You need to 'vacuum analyze <table>' for each table that you have created AFTER you've created the indexes for them before the sql optimizer will use the indexes. This should solve most of your speed issues. I also believe that this is in the FAQ. -=pierre