Re: slight tweaks to documentation about runtime pruning

On 2018-Dec-10, David Rowley wrote:

> On Wed, 5 Dec 2018 at 20:24, Amit Langote <Langote_Amit_f8(at)lab(dot)ntt(dot)co(dot)jp> wrote:

> > However, for pruned partitions' subplans, what's actually shown is the
> > string "(never executed)", not loops. So, wouldn't it be better to tell
> > the readers to look for that instead of "loops"?
>
> I don't really see any issues with the existing documentation here.
> Remember that pruning can be performed multiple times when a parameter
> changes that was found to match the partition key and the
> Append/MergeAppend is rescanned.

I lean towards Amit's side. I think we're too laconic about many
details of EXPLAIN's output. This is two lines about an interesting
detail that's pretty obscure. It doesn't hurt to have it there.

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Álvaro Herrera https://www.2ndQuadrant.com/
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