Miroslav Šulc wrote:
> is there on the net any general howto on SQL query optimizations? We
> have recently moved our project from MySQL to PostgreSQL and are
> having problem with one of our queries.
I doubt that there is a generic documentation on SQL optimization,
because this heavily depends on the particular implementation that you
are using.
> The EXPLAIN command is surely
> useful but I don't know how to read it and how to use the output to
> optimize the query so I'm looking for some intro that could help me.
You should probably start with the Performance Tips chapter in the
PostgreSQL documentation.
--
Peter Eisentraut
http://developer.postgresql.org/~petere/