Re: Problem with default partition pruning - Mailing list pgsql-hackers

From Amit Langote
Subject Re: Problem with default partition pruning
Date
Msg-id fa6ba10b-2123-22b6-8888-e6a3ec84101a@lab.ntt.co.jp
Whole thread Raw
In response to Re: Problem with default partition pruning  (Thibaut Madelaine <thibaut.madelaine@dalibo.com>)
Responses RE: Problem with default partition pruning
List pgsql-hackers
Hi,

On 2019/03/23 2:36, Thibaut Madelaine wrote:
> I tested your last patch and if I didn't mix up patches on the end of a
> too long week, I get a problem when querying the sub-sub partition:
> 
> test=# explain select * from test2_0_10 where id = 25;
>                          QUERY PLAN                        
> ------------------------------------------------------------
>  Seq Scan on test2_0_10  (cost=0.00..25.88 rows=6 width=36)
>    Filter: (id = 25)
> (2 rows)

The problem here is not really related to partition pruning, but another
problem I recently sent an email about:

https://www.postgresql.org/message-id/9813f079-f16b-61c8-9ab7-4363cab28d80%40lab.ntt.co.jp

The problem in this case is that *constraint exclusion* is not working,
because partition constraint is not loaded by the planner.  Note that
pruning is only used if a query specifies the parent table, not a partition.

Thanks,
Amit



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