Re: Proposal: scan key push down to heap [WIP]

On Sat, Dec 3, 2016 at 10:30 AM, Dilip Kumar <dilipbalaut@gmail.com> wrote:
>> I'll post my new expression evaluation stuff - which doesn't do this
>> atm, but makes ExecQual faster in other ways - later this week.  If we
>> could get the planner (or parse-analysis?) to set an OpExpr flag that
>> signals that the expression can be evaluated as a scankey, that'd be
>> easy.
>
> Isn't it better to directly make two separate lists during planning
> itself, one for regular qual and other which can be converted to
> scankey. Instead of keeping the flag in OpExpr ?

Well, I certainly think that in the end we need them in two separate
lists.  But it's possible that a flag in the OpExpr could somehow be
useful in constructing those lists cheaply.  I'm not sure I see what
Andres has in mind, though.

-- 
Robert Haas
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