Horton

Re: Partition-wise join for join between (declaratively) partitioned tables

Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>

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From: Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>
To: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
Cc: Robert Haas <robertmhaas@gmail.com>, Etsuro Fujita <fujita.etsuro@lab.ntt.co.jp>, Thomas Munro <thomas.munro@enterprisedb.com>, Rafia Sabih <rafia.sabih@enterprisedb.com>, Rajkumar Raghuwanshi <rajkumar.raghuwanshi@enterprisedb.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2017-09-13T07:30:17Z
Lists: pgsql-hackers 
On Wed, Sep 13, 2017 at 11:29 AM, Amit Langote
<Langote_Amit_f8@lab.ntt.co.jp> wrote:
> On 2017/09/12 19:56, Ashutosh Bapat wrote:
>> I think the code here expects the original parent_rte and not the one
>> we set around line 1169.
>>
>> This isn't a bug right now, since both the parent_rte s have same
>> content. But I am not sure if that will remain to be so. Here's patch
>> to fix the thinko.
>
> Instead of the new bool is_parent_partitioned, why not move the code to
> set partitioned_rels to the block where you're now setting
> is_parent_partitioned.
>
> Also, since we know this isn't a bug at the moment but will turn into one
> once we have step-wise expansion, why not include this fix in that patch
> itself?

It won't turn into a bug with step-wise expansion since every
parent_rte will have RELKIND_PARTITIONED_TABLE for a partitioned top
parent, which is used to extract the partitioned_rels. But I guess,
it's better to fix the thinko in step-wise expansion since parent_rte
itself changes.
-- 
Best Wishes,
Ashutosh Bapat
EnterpriseDB Corporation
The Postgres Database Company

Commits

  1. Add test for partitionwise join involving default partition.

  2. Rewrite the code that applies scan/join targets to paths.

  3. Fix code related to partitioning schemes for dropped columns.

  4. Copy information from the relcache instead of pointing to it.

  5. Basic partition-wise join functionality.

  6. Associate partitioning information with each RelOptInfo.

  7. Expand partitioned table RTEs level by level, without flattening.

  8. Set partitioned_rels appropriately when UNION ALL is used.

  9. Remove dedicated B-tree root-split record types.

  10. Assorted preparatory refactoring for partition-wise join.

  11. Teach adjust_appendrel_attrs(_multilevel) to do multiple translations.

  12. Avoid unnecessary single-child Append nodes.

  13. Revisit handling of UNION ALL subqueries with non-Var output columns.