Re: PG11 - Multiple Key Range Partition - Mailing list pgsql-bugs
Hi David,
I tested out your example and all works fine for me as well. But I live the main issue lies in the following example:
create table rangep (a bool, b bool, c date) partition by range (a,b,c);
create table rangep1_recent partition of rangep for values from (true,false, '1990-01-01') to (true,false,'2090-01-01');
create table rangep1_deleted partition of rangep for values from (false,true, '1990-01-01') to (false,true,'2090-01-01');
create table rangep1_2019 partition of rangep for values from (false,false, '2019-01-01') to (false,false,'2020-01-01');
create table rangep1_2018 partition of rangep for values from (false,false, '2018-01-01') to (false,false,'2019-01-01');
create table rangep1_2017 partition of rangep for values from (false,false, '2017-01-01') to (false,false,'2018-01-01');
create table rangep1_2019 partition of rangep for values from (false,false, '2019-01-01') to (false,false,'2020-01-01');
create table rangep1_2018 partition of rangep for values from (false,false, '2018-01-01') to (false,false,'2019-01-01');
create table rangep1_2017 partition of rangep for values from (false,false, '2017-01-01') to (false,false,'2018-01-01');
explain select * from rangep where not a and not b and c = '2019-07-10';
When doing:
explain select * from rangep where a and not b an and c = '2019-07-10';
or simply
explain select * from rangep where a and c = '2019-07-10';
It successfully searches only in the 'recent' partition.
I believe the planner gets confused when we introduce the following two combinations: (true, false, '1990-01-01') - (true, false, '2090-01-01') and (false, true, '1990-01-01') - (false, true, '2090-01-01').
My current Postgres version is PostgreSQL 11, 2.2.4. ("PostgreSQL 11.4 on x86_64-apple-darwin16.7.0, compiled by Apple LLVM version 8.1.0 (clang-802.0.42), 64-bit")
Thank you for the quick response, I’m eager to receive your feedback.
Have a great day!
Rares
On Wed, Jul 10, 2019 at 2:33 AM David Rowley <david.rowley@2ndquadrant.com> wrote:
On Tue, 9 Jul 2019 at 18:53, Rares Salcudean
<rares.salcudean@takeofflabs.com> wrote:
> The example you suggested:
>
> explain select * from scores where NOT(recent = true) and NOT(deleted = true) and played_at = '2018-03-02'
> explain select * from scores where NOT(recent) and NOT(deleted) and played_at = '2018-03-02'
>
> Yield the same result:
Works okay for me with:
create table rangep (a bool, b bool, c date) partition by range (a,b,c);
create table rangep1 partition of rangep for values from (false,
false, '2019-01-01') to (false,false,'2020-01-01');
create table rangep2 partition of rangep for values from (true, true,
'2019-01-01') to (true,true,'2020-01-01');
explain select * from rangep where not a and not b and c = '2019-07-10';
QUERY PLAN
--------------------------------------------------------------
Seq Scan on rangep1 (cost=0.00..40.00 rows=3 width=6)
Filter: ((NOT a) AND (NOT b) AND (c = '2019-07-10'::date))
(2 rows)
That's on master, but v10 and v11 still prune away rangep2.
It might help if you share which version you're using and a cutdown
version of the schema, just enough to show the issue.
--
David Rowley http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services
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