Ehab Galal <ehabgalal123@hotmail.com> writes: > what i expected is that the optimizer will use the redundant predicates > to create the plan, but the execution plan itself will not execute a > redundant predicate. > O! I see, it's my mistake. The example i mentioned was not a good example. I tried the equality and it is working well :) The planner has a great deal more smarts about equality conditions than inequality conditions. There's more you can do with equalities, and it's more useful for typical queries. > I am using postgresql 8.5.1, I am wondering is there is any patch that > i can run to enable it to put the actual table names instead of > inner/outer. Update to 8.2. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match