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: Rajkumar Raghuwanshi <rajkumar.raghuwanshi@enterprisedb.com>, Robert Haas <robertmhaas@gmail.com>, Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>, Jesper Pedersen <jesper.pedersen@redhat.com>, Amit Langote <amitlangote09@gmail.com>, Dilip Kumar <dilipbalaut@gmail.com>, Beena Emerson <memissemerson@gmail.com>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2018-02-22T11:28:13Z
Lists: pgsql-hackers 
On 22 February 2018 at 22:48, Amit Langote
<Langote_Amit_f8@lab.ntt.co.jp> wrote:
>> I'm having to add some NULL handling there for the run-time pruning
>> patch but wondered if it was also required for your patch.
>
> Hmm, not sure why.  Can you explain a bit more?

hmm, yeah, but perhaps we should be discussing on the other thread...

With a prepared statement the Param will be unavailable until
execution, in which case we don't do the const folding.

A simple case is:

create table listp (a int) partition by list (a);
create table listp1 partition of listp for values in(1);
prepare q1 (int) as  select * from listp where a = $1;
explain analyze execute q1(1); -- repeat 5 times.
explain analyze execute q1(null); -- partkey_datum_from_expr() gets a
NULL param via the call from nodeAppend.c


-- 
 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.