On Tue, Feb 07, 2006 at 08:07:53AM -0500, [EMAIL PROTECTED] wrote: > It is also interesting to note that PostgreSQL get significantly > slower in Test 13 (join with an index) versus Test 6 (the same > join without an index). What is that about? Firebird shows the > same effect, but less dramatically. Could it be a difference in > the data that the tables hold at that point. Test 6B proposed > above really would be instructive here, I think.
Well, I'm a bit skeptical as to the usefulness of that test, since if I'm reading things correctly it's essentially a cartesian product. In any case, it's very likely that the lack of analysis and default parameters resulted in a bad query plan. The output of EXPLAIN ANALYZE would be most instructive. > I also wonder if MySQL and Firebird would benefit from tuning. > The MySQL people are rather laid back and probably will say > something like "whatever" if asked. The Firebird crowd, on the > other hand, tend to be edgy and I suspect we will be hearing > some pointed commentary from them in the near future. FWIW, I wouldn't really consider the changes I suggested 'tuning', as they're rather off-the-cuff based strictly on my experience and limited knowledge as to the workload. Personally, I'd prefer if PostgreSQL would at least provide multiple sample configs, but c'est la vie. AFAIK MySQL ships with a few different config files, so presumably choosing the appropriate one would be equivalent to what I provided for PostgreSQL. BTW, has anyone looked at adding SQLite support to any of the DBT benchmarks? http://sourceforge.net/projects/osdldbt -- Jim C. Nasby, Sr. Engineering Consultant [EMAIL PROTECTED] Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461
