Horton

Re: speeding up planning with partitions

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Amit Langote <amitlangote09@gmail.com>, Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>, David Rowley <david.rowley@2ndquadrant.com>, Imai Yoshikazu <yoshikazu_i443@live.jp>, "jesper.pedersen@redhat.com" <jesper.pedersen@redhat.com>, "Imai, Yoshikazu" <imai.yoshikazu@jp.fujitsu.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Justin Pryzby <pryzby@telsasoft.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2019-03-30T15:36:56Z
Lists: pgsql-hackers 
On Sat, Mar 30, 2019 at 11:11 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Before that, though, I remain concerned that the PartitionPruneInfo
> data structure the planner is transmitting to the executor is unsafe
> against concurrent ATTACH PARTITION operations.  The comment for
> PartitionedRelPruneInfo says in so many words that it's relying on
> indexes in the table's PartitionDesc; how is that not broken by
> 898e5e329?

The only problem with PartitionPruneInfo structures of which I am
aware is that they rely on PartitionDesc offsets not changing. But I
added code in that commit in ExecCreatePartitionPruneState to handle
that exact problem.  See also paragraph 5 of the commit message, which
begins with "Although in general..."

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

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.