Andre, > http://candle.pha.pa.us/main/writings/pgsql/hw_performance/ > brought some light over the subject. For few users, could be a viable > alternative. That article is very old. Read this instead: http://www.powerpostgresql.com/PerfList > select count(distinct NF.ID_NF ) as contagem, DE.AM_REFERENCIA as campo > from DECLARACAO DE inner join CADASTRO CAD on > (CAD.ID_DECLARACAO=DE.ID_DECLARACAO) > inner join NOTA_FISCAL NF on (NF.ID_CADASTRO=CAD.ID_CADASTRO) > inner join EMPRESA EMP on (EMP.ID_EMPRESA=DE.ID_EMPRESA) > inner join ARQUIVO_PROCESSADO ARQ on (ARQ.ID_ARQUIVO=DE.ID_ARQUIVO) > group by DE.AM_REFERENCIA > order by DE.AM_REFERENCIA > > firebird windows executed in 1min30s > postgresql windows is running for 3 hours and still not finished. How about an EXPLAIN? And, did you run ANALYZE on the data? > I already know that count() is VERY performance problematic in > postgresql. Is there a way to work around this? > Unfortunately, the deadline for my friend project is approaching and he > is giving up postgresql for firebird. > If some work around is available, he will give another try. But i > already saw that count and joins are still problem. > He asked me if other people are struggling with poor performance and > wondered if all other users are issuing simple queries only. No, actually we excel at complex queries. Some of the data warehousing stuff I run involves queries more than a page long. Either you're hitting some Windows-specific problem, or you still have some major basic tuning issues. That being said, there's nothing wrong with Firebird if he wants to use it. -- --Josh Josh Berkus Aglio Database Solutions San Francisco
