Re: enable_joinremoval

Tom Lane escribió:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> > On Mon, Mar 29, 2010 at 4:33 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> >> So I think we need a parameter for join removal also.
>
> > I had this in my original patch but Tom wanted it taken out.
>
> And I still don't want it. We are NOT going in the direction of adding
> an enable_ knob for every single planner activity --- do you have the
> faintest idea how many there would be? We have such knobs for a small
> number of cases where it's arguable that the action might be the wrong
> thing for a particular query. Join removal, if applicable, can't
> possibly be the wrong choice; it's better than every other join strategy.

It seems that what's really needed is some debug output to be able to
find out what it did.

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Alvaro Herrera http://www.CommandPrompt.com/
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