Re: slight tweaks to documentation about runtime pruning
Alvaro Herrera <alvherre@2ndquadrant.com>
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: David Rowley <david.rowley@2ndquadrant.com>
Cc: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2018-12-16T22:30:10Z
Lists: pgsql-hackers
On 2018-Dec-10, David Rowley wrote: > On Wed, 5 Dec 2018 at 20:24, Amit Langote <Langote_Amit_f8@lab.ntt.co.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. -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
Commits
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Clarify runtime pruning in EXPLAIN
- 1e6240a3fe91 12.0 landed
- f760a8b5cc1f 11.2 landed