Re: One Partition by list is always chosen by planner - Mailing list pgsql-general

From legrand legrand
Subject Re: One Partition by list is always chosen by planner
Date
Msg-id 1511337694391-0.post@n3.nabble.com
Whole thread Raw
In response to Re: One Partition by list is always chosen by planner  (Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>)
List pgsql-general
Hello,

thank you for this answer.
I just wanted to add a few informations.

This table has in fact around 20 partitions,

explain select * from wiki_data_part where category='fr' 
returns only 2 partitions (meaning that constraint_exclusion works)

the partition that is always scanned has more than 100 distinct values in
its partition list.

After splitting this partition into 2 partitions the problem is gone ...

For me this is as if the planner was not able to check partitions with too
much values.
There is no error with the query result, just a limited impact on
performances.

Regards
PAscal




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