Horton

Re: [HACKERS] path toward faster partition pruning

David Rowley <david.rowley@2ndquadrant.com>

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From: David Rowley <david.rowley@2ndquadrant.com>
To: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
Cc: Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>, Rajkumar Raghuwanshi <rajkumar.raghuwanshi@enterprisedb.com>, Robert Haas <robertmhaas@gmail.com>, Dilip Kumar <dilipbalaut@gmail.com>, Beena Emerson <memissemerson@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2017-12-21T11:17:50Z
Lists: pgsql-hackers 
On 21 December 2017 at 23:38, Amit Langote
<Langote_Amit_f8@lab.ntt.co.jp> wrote:
> On 2017/12/20 17:27, Amit Langote wrote:
> I think I was able to make this work and in the process of making it work,
> also came to the conclusion that this could be made to work sensibly
> *only* for list partitioned tables.  That's because one cannot prune a
> given partition using a set of <> operator clauses, if we cannot be sure
> that those clauses exclude *all* values of the partition key allowed by
> that partition.  It's only possible to do that for a list partitioned
> table, because by definition one is required to spell out every value that
> a given partition of such table allows.

Makes sense. Thanks for fixing LIST partitioning to work with that.

We have no way to know that there's no value between 1::int and
2::int, so it's completely understandable why this can't work for
RANGE. HASH is also understandable since we don't have a complete
picture of all the values that can be contained within the partition.

I'll try to do another complete review of v16 soon.

-- 
 David Rowley                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services

Commits

  1. Fix assorted partition pruning bugs

  2. Make gen_partprune_steps static

  3. Remove useless 'default' clause

  4. Reorganize partitioning code

  5. Use custom hash opclass for hash partition pruning

  6. Blindly attempt to fix sepgsql tests broken due to 9fdb675fc5.

  7. Attempt to fix endianess issues in new hash partition test.

  8. Faster partition pruning

  9. For partitionwise join, match on partcollation, not parttypcoll.

  10. Revise API for partition bound search functions.

  11. Revise API for partition_rbound_cmp/partition_rbound_datum_cmp.

  12. Fix possible crash in partition-wise join.

  13. Refactor code for partition bound searching

  14. New C function: bms_add_range

  15. Add extensive tests for partition pruning.

  16. Add null test to partition constraint for default range partitions.

  17. Remove BufFile's isTemp flag.

  18. Make OWNER TO subcommand mention consistent

  19. Fix index matching for operators with mixed collatable/noncollatable inputs.