Re: Using multiple extended statistics for estimates

On Sun, Dec 01, 2019 at 08:08:58PM +0100, Tomas Vondra wrote:
>On Sat, Nov 30, 2019 at 03:01:31PM -0800, Mark Dilger wrote:
>>
>>Are you planning to submit a revised patch for this?
>>
>
>Yes, I'll submit a rebased version of this patch shortly. I got broken
>because of the recent fix in choose_best_statistics, shouldn't take long
>to update the patch. I do have a couple more related patches in the
>queue, so I want to submit them all at once.
>

OK, here we go - these two patched allow applying multiple extended
statistics, both for MCV and functional dependencies. Functional
dependencies are simply merged and then applied at once (so withouth
choose_best_statistics), statistics are considered in greedy manner by
calling choose_best_statistics in a loop.

I do have some additional enhancements in the queue, but those are not
fully baked yet, so I'll post them later in separate patches.

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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