pgsql-odbc doesn't seem a right place to post. I forwarded my reply to pgsql-hackers also.
Michael Rudolph wrote: > > Hi, > > I have a performance-problem with my Postgresql-database: up to now I > had centura sqlbase but for some reasons I have to change to Postgres. > After copying the data of an existing database I made some tests for > performance which where very disappointing. There is one table, let's > say table1, with about 11.0000 rows. On doing a "select distinct var1 > from table1" via ODBC-Driver, I had to wait about 15 sec for the result. > The same select on centura sqlbase lasted about 3 sec. Ok, I thought, it > might be the ODBC-Driver with that bad performance and I did that query > directly with psql. Not much better, it lasted around 10 sec. > How many rows are returned by the query in reality ? Does the table *table1* have an index on the column *var1* in your centura sqlbase ? > This isn't what I can give to my users because in my application I have > to do a lot of queries of that kind. The users would have a lot of time > to hang around, waiting for the application, and thinking, how to kill > me ;-) . > > I made some more tests with indices and with more indices but the > improvement is not worth to mention. > > I am now at a point, wondering, if the transfer from centura to postgres > is the right way but I can't imagine why the performance of centura is > so much better. The conditions are nearly the same (256 MB RAM, Pentium > III) beside of the OS, which is Novell Netware for Centura and Linux > (Kernel 2.4.0) for Postgres. The version of Postgres is 7.0.3. > > Does anybody have an idea what else I can do? Thank yo very much for > your help. > > Michael ---------------------------(end of broadcast)--------------------------- TIP 4: Don't 'kill -9' the postmaster
