Horton

Re: [HACKERS] advanced partition matching algorithm for partition-wise join

amul sul <sulamul@gmail.com>

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From: amul sul <sulamul@gmail.com>
To: Etsuro Fujita <etsuro.fujita@gmail.com>
Cc: Thomas Munro <thomas.munro@gmail.com>, Robert Haas <robertmhaas@gmail.com>, Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>, Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>, Rajkumar Raghuwanshi <rajkumar.raghuwanshi@enterprisedb.com>, Etsuro Fujita <fujita.etsuro@lab.ntt.co.jp>, Dmitry Dolgov <9erthalion6@gmail.com>, Thomas Munro <thomas.munro@enterprisedb.com>, Antonin Houska <ah@cybertec.at>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2019-07-19T11:09:19Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Suppress unused-variable warning.

  2. Allow partitionwise joins in more cases.

  3. Avoid crash in partitionwise join planning under GEQO.

  4. Disable support for partitionwise joins in problematic cases.

  5. Add plan_cache_mode setting

  6. Add test for partitionwise join involving default partition.

  7. Revise API for partition_rbound_cmp/partition_rbound_datum_cmp.

On Mon, Jul 8, 2019 at 5:03 PM Etsuro Fujita <etsuro.fujita@gmail.com>
wrote:

> On Wed, Jul 3, 2019 at 3:44 PM Etsuro Fujita <etsuro.fujita@gmail.com>
> wrote:
> > On Tue, Jul 2, 2019 at 1:47 PM amul sul <sulamul@gmail.com> wrote:
> > > Attached version is rebase atop of the latest master head(c74d49d41c),
> thanks.
> >
> > Thanks!  Will review.
>
> I started reviewing this.  Here is my initial review comments:
>
> * 0001-Hash-partition-bound-equality-refactoring-v22.patch
>
> First of all, I agree with your view on hash partitioning:
>
> "3. For hash partitioned tables however, we support partition-wise join
> only when the bounds exactly match. For hash partitioning it's unusual
> to have missing partitions and hence generic partition matching is not
> required."
>
> which is cited from the commit message for the main patch
> "0002-Partition-wise-join-for-1-1-1-0-0-1-partition-matchi-v22.patch".
> (I think it would be better if we can extend the partition matching to
> the hash-partitioning case where there are missing partitions in
> future, though.)  However, I don't think it's a good idea to do this
> refactoring, because that would lead to duplicating the code to check
> whether two given hash bound collections are equal in
> partition_bounds_equal() and partition_hash_bounds_merge() that will
> be added by the main patch, after all.  To avoid that, how about
> calling partition_bounds_equal() from partition_hash_bounds_merge() in
> the main patch, like the attached?


Agree, your changes look good to me, thanks for working on it.

Regards,
Amul