Re: Condition pushdown: why (=) is pushed down into join, but BETWEEN or >= is not?

>
>
> I don't think 0001 is right either, although maybe for somewhat
> different reasons. First, I think it only considers VAR OP CONST style
> clauses, but that is leaving money on the table, because given a.x =
> b.x AND mumble(a.x), we can decide to instead test mumble(b.x) if the
> equality operator in question has is-binary-identical semantics. It
> does not seem necessary for a first patch to deal with both that and
> the somewhat more pleasing case where we're making deductions based on
> operator families ... but we shouldn't commit to a design for the VAR
> OP CONST case without understanding how it could be generalized.
>

I can follow up with this and +1 with the statement.

> Second, it looks to me like the patch takes the rather naive strategy
> of enforcing the derived clauses everywhere that they can legally be
> put, which seems certain not to be optimal.

If we can have some agreement (after more discussion) the EC filter is
acceptable on semantics level, I think we may have some chances to
improve something at execution level.

--
Best Regards
Andy Fan