On Tue, 2007-05-08 at 08:08 -0400, Marshall, Steve wrote: > I think the optimization could work if you could exclude prepared > statements. However, I looked at the planning code and found no clear > way to distinguish between a statement being prepared for later > execution, and a statement being planned only for immediate execution. > As a result, I don't think stable functions can (or should) be > expanded to help optimize queries using constraint exclusion.
I think it should be possible to tell the difference between planned and immediate-execution queries. Anything coming thru exec_simple_query can be tagged as immediate-execution, so should be allowed to make the evaulation of stable functions in the planner as being accurate for the rest of the statement execution also. -- Simon Riggs EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster