Re: speeding up planning with partitions

On Fri, 22 Mar 2019 at 20:39, Amit Langote
<Langote_Amit_f8@lab.ntt.co.jp> wrote:
> The problem is that make_partitionedrel_pruneinfo() does some work which
> involves allocating arrays containing nparts elements and then looping
> over the part_rels array to fill values in those arrays that will be used
> by run-time pruning.  It does all that even *before* it has checked that
> run-time pruning will be needed at all, which if it is not, it will simply
> discard the result of the aforementioned work.
>
> Patch 0008 of 0009 rearranges the code such that we check whether we will
> need run-time pruning at all before doing any of the work that's necessary
> for run-time to work.

I had a quick look at the make_partitionedrel_pruneinfo() code earlier
before this patch appeared and I agree that something like this could
be done. I've not gone over the patch in detail though.

-- 
 David Rowley                   http://www.2ndQuadrant.com/
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