Re: explain (verbose off, normalized) vs query planid - Mailing list pgsql-hackers

From Tom Lane
Subject Re: explain (verbose off, normalized) vs query planid
Date
Msg-id 21912.1526418148@sss.pgh.pa.us
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In response to Re: explain (verbose off, normalized) vs query planid  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes:
> On Tue, May 15, 2018 at 3:45 PM, legrand legrand
> <legrand_legrand@hotmail.com> wrote:
>> Would there be some functional or performances reasons to prefer jumbling to
>> hashing normalized plan text?

> Basically, I would be nervous about the idea of an EXPLAIN output
> that's required to reflect all and only the plan details that should
> be jumbled.  The "normalized" option to EXPLAIN which you mentioned
> upthread doesn't exist today...

Indeed, and if we did write it, I think it would largely consist of
throwing away info that a jumbling mechanism could ignore far more easily.
Not to mention that we'd have to expend the cycles to emit a text
representation that we didn't actually have use for.  It sounds like a
complete loser both in terms of coding effort and runtime performance.

            regards, tom lane


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