Horton

Re: speeding up planning with partitions

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
Cc: Imai Yoshikazu <yoshikazu_i443@live.jp>, "jesper.pedersen@redhat.com" <jesper.pedersen@redhat.com>, "Imai, Yoshikazu" <imai.yoshikazu@jp.fujitsu.com>, "'Amit Langote'" <amitlangote09@gmail.com>, David Rowley <david.rowley@2ndquadrant.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Robert Haas <robertmhaas@gmail.com>, Justin Pryzby <pryzby@telsasoft.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2019-03-26T22:26:31Z
Lists: pgsql-hackers 
Amit Langote <Langote_Amit_f8@lab.ntt.co.jp> writes:
> On 2019/03/23 6:07, Tom Lane wrote:
>> I also feel like you used a dartboard while deciding where to insert the
>> call in query_planner(); dropping it into the middle of a sequence of
>> equivalence-class-related operations seems quite random.  Maybe we could
>> delay that step all the way to just before make_one_rel, since the other
>> stuff in between seems to only care about baserels?  For example,
>> it'd certainly be better if we could run remove_useless_joins before
>> otherrel expansion, so that we needn't do otherrel expansion at all
>> on a table that gets thrown away as being a useless join.

> create_lateral_join_info() expects otherrels to be present to propagate
> the information it creates.

Sure, but the actually-useful work in that function is just concerned
with baserels.  The only thing it does with otherrels is to propagate
parents' lateral-ref info to children, which is a lot easier, cheaper,
and more reliable if we let build_simple_rel do it.  See the version
of 0001 I just pushed.

I'll look at 0003 and up tomorrow.

			regards, tom lane

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.