> > I don't chime in very often, but I do think the refusal to incorporate > > hints into the planner system is fantastically stubborn and > > nonsensical. > > What is actually fantastically nonsensical about this is that > the issues I outlined about prepared statements would merely > become worse if planner hints were used. Then, you wouldn't > only have to worry about plans that were created earlier > during the session, you would be faced with plans that were > created earlier during the application's development. In > general, the solutions to the prepared statement issues need > to effect that the plans are created more often, not less often.
I have yet to see one of our partial Informix hints (where the planner does it's usual job only with one path with lowered/elevated costs) fall foul on not anticipated change of underlying data. Thus I don't buy the argument that hints are always bad. Of course their use should be extremely rare and well thought out. Most of the time sql tuning involves a concerted effort between the programmer and a db performance expert, usually resulting in rewritten sql or program logic without adding hints. I can see arguments for hints the dba can set himself centrally on the server, but in my experience chances for substantial improvement are very limited in that case. Andreas ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq