Re: Proposal: scan key push down to heap [WIP] - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Proposal: scan key push down to heap [WIP]
Date
Msg-id 28385.1477415927@sss.pgh.pa.us
Whole thread Raw
In response to Re: Proposal: scan key push down to heap [WIP]  (Alvaro Herrera <alvherre@2ndquadrant.com>)
Responses Re: Proposal: scan key push down to heap [WIP]  (Andres Freund <andres@anarazel.de>)
List pgsql-hackers
Alvaro Herrera <alvherre@2ndquadrant.com> writes:
> BTW, should we cost push-down-able quals differently, say discount some
> fraction of the cost, to reflect the fact that they are cheaper to run?
> However, since the decision of which ones to push down depends on the
> cost, and the cost would depend on which ones we push down, it looks
> rather messy.

I don't think our cost model is anywhere near refined enough to make it
worth trying to distinguish that.  (Frankly, I'm pretty skeptical of this
entire patch being worth the trouble...)
        regards, tom lane



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