Horton

RE: speeding up planning with partitions

Imai, Yoshikazu <imai.yoshikazu@jp.fujitsu.com>

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From: "Imai, Yoshikazu" <imai.yoshikazu@jp.fujitsu.com>
To: "Imai, Yoshikazu" <imai.yoshikazu@jp.fujitsu.com>, 'Amit Langote' <Langote_Amit_f8@lab.ntt.co.jp>
Cc: 'Amit Langote' <amitlangote09@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, David Rowley <david.rowley@2ndquadrant.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Justin Pryzby <pryzby@telsasoft.com>, Pg Hackers <pgsql-hackers@postgresql.org>, Jesper Pedersen <jesper.pedersen@redhat.com>
Date: 2019-03-15T05:40:26Z
Lists: pgsql-hackers 
Amit-san,

I have another little comments about v31-patches.

* We don't need is_first_child in inheritance_planner().

On Fri, Mar 8, 2019 at 9:18 AM, Amit Langote wrote:
> On 2019/03/08 16:16, Imai, Yoshikazu wrote:
> > I attached the diff of modification for v26-0003 patch which also
> contains some refactoring.
> > Please see if it is ok.
> 
> I like the is_first_child variable which somewhat improves readability,
> so updated the patch to use it.

I noticed that detecting first child query in inheritance_planner() is already done by "final_rtable == NIL"

        /*
         * If this is the first non-excluded child, its post-planning rtable
         * becomes the initial contents of final_rtable; otherwise, append
         * just its modified subquery RTEs to final_rtable.
         */
        if (final_rtable == NIL)

So I think we can use that instead of using is_first_child.

--
Yoshikazu Imai

Commits

  1. Clean up handling of constraint_exclusion and enable_partition_pruning.

  2. Add test case exercising formerly-unreached code in inheritance_planner.

  3. Speed up planning when partitions can be pruned at plan time.

  4. Avoid crash in partitionwise join planning under GEQO.

  5. Avoid passing query tlist around separately from root->processed_tlist.

  6. Build "other rels" of appendrel baserels in a separate step.

  7. Get rid of duplicate child RTE for a partitioned table.

  8. Rearrange make_partitionedrel_pruneinfo to avoid work when we can't prune.

  9. Don't copy PartitionBoundInfo in set_relation_partition_info.

  10. Move building of child base quals out into a new function

  11. Reorganize planner code moved in b60c39759908

  12. Move inheritance expansion code into its own file

  13. Fix inherited UPDATE/DELETE with UNION ALL subqueries.

  14. Rearrange planner to save the whole PlannerInfo (subroot) for a subquery.