Re: Should we add GUCs to allow partition pruning to be disabled?

On Fri, May 18, 2018 at 4:22 AM, Amit Langote
<Langote_Amit_f8@lab.ntt.co.jp> wrote:
> Yeah, I think it'd help to have Append be annotated as suggested by Robert
> above.  I guess if "at executor startup" is shown, then the subnodes
> listed under Append will consist of only those that survived
> executor-startup pruning and thus will help understand why there are fewer
> than shown with EXPLAIN (without ANALYZE).  Also, if "at runtime" is
> shown, a user may want look at nloops property of the individual subnodes
> to guess at how much pruning has occurred; although only the latter (that
> is, inspecting nloops) suffices to know that runtime pruning has occurred
> as also currently written in the documentation about pruning [1], the
> first piece of information (the "at runtime" annotation) seems nice to have.

Having EXPLAIN and EXPLAIN ANALYZE show different things doesn't sound
like a good idea.

-- 
Robert Haas
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