Re: parameter hints to the optimizer

Oliver Jowett wrote:
> Bruce Momjian wrote:
> > Oliver Jowett wrote:
> > 
> >>Merlin Moncure wrote:
> >>
> >>
> >>>Another way to deal with the problem is to defer plan generation until
> >>>the first plan execution and use the parameters from that execution.
> >>
> >>When talking the V3 protocol, 7.5 defers plan generation for the unnamed 
> >>statement until parameters are received in the Bind message (which is 
> >>essentially the same as what you describe). There was some discussion at 
> >>the time about making it more flexible so you could apply it to arbitary 
> >>statements, but that needed a protocol change so it didn't happen.
> > 
> > 
> > What do you mean about arbitrary statements?  Non-prepared ones, or
> > non-unnamed ones?
> 
> Non-unnamed ones. Adding flag on the Parse message that says when to 
> plan the statement (or maybe on each Bind message even).

OK, what are unnamed prepared statements?  When are they used currently?
Only via the wire protocol?  Who uses them now?

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