On Thu, Jun 2, 2011 at 2:56 PM, Claudio Freire <klaussfreire@xxxxxxxxx> wrote: > On Thu, Jun 2, 2011 at 4:57 PM, Kevin Grittner > <Kevin.Grittner@xxxxxxxxxxxx> wrote: >> And the >> planner does take the size of work_mem and the expected data set >> into consideration when estimating the cost of the hash join. > > And shouldn't it? > > In a gross mode, when hash joins go to disk, they perform very poorly. > Maybe the planner should take that into account. It does. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
