Re: Implied Functional index use (redux) - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Implied Functional index use (redux)
Date
Msg-id 24443.1169827121@sss.pgh.pa.us
Whole thread Raw
In response to Re: Implied Functional index use (redux)  ("Simon Riggs" <simon@2ndquadrant.com>)
Responses Re: Implied Functional index use (redux)  ("Simon Riggs" <simon@2ndquadrant.com>)
List pgsql-hackers
"Simon Riggs" <simon@2ndquadrant.com> writes:
> If there's clear benefit and a clear way forward, then we might just be
> OK for 8.3. If not, I'll put this back on the shelf again in favour of
> other ideas.

I think this is still a long way off, and there are probably more useful
things to work on for 8.3.

Part of my antagonism stems from the fact that by means of the operator
family rewrite I've been getting rid of some longstanding but really
quite unacceptable assumptions about "this operator does that".  I don't
want to see us start putting unsupported semantic assumptions back into
the optimizer; rather its assumptions about operator behavior need to be
clearly specified.  As an example, without some careful preliminary
thinking I'd have probably folded all the numeric types into one big
opfamily and thereby broken transitivity :-(, leading to bugs that would
be devilish to figure out.
        regards, tom lane


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