Re: [HACKERS] Partitioned tables and relfilenode

>>
>> Will it help to retain the partition hierarchy as inheritance
>> hierarchy and then collapse it while creating append paths. That will
>> be needed by partition-wise join, will be helpful in partition pruning
>> without using constraints and so on. So, may be could use that
>> infrastructure to simplify the logic here. The patch is available as
>> 0013 in [1].
>>
>> [1] CAFjFpRfqotRR6cM3sooBHMHEVdkFfAZ6PyYg4GRZsoMuW08HjQ@mail.gmail.com
>
> IMHO, it would be better to keep those patches separate because the
> problems being solved are different.  By the way, one of the reasons that
> patch (as I had written it) was skipped was because it didn't cover the
> inheritance_planner() case [1].  Your patch 0013 at the link should be
> updated (maybe I should report on the partitionwise joins thread as well)
> in some way to handle the update/delete case, because this happens:
>
> create table p (a int, b char) partition by list (a);
> create table p1 partition of p for values in (1) partition by list (b);
> create table p1a partition of p1 for values in ('a');
> create table p2 partition of p for values in (2);
>
> explain (costs off) update p set a = a, b = 'b';
>             QUERY PLAN
> -----------------------------------
>  Update on p
>    Update on p
>    Update on p1 p
>    Update on p2
>    ->  Seq Scan on p
>    ->  Result
>          ->  Append
>                ->  Seq Scan on p1
>                ->  Seq Scan on p1a
>    ->  Seq Scan on p2
> (10 rows)
>
> update p set a = a, b = 'b';
>         server closed the connection unexpectedly
>         This probably means the server terminated abnormally
>         before or while processing the request.
> The connection to the server was lost. Attempting reset: Failed.

Thanks for pointing that out. I am able to reproduce the crash. I
think, we will need to teach it to add the indirect children as well.
Looks like we are missing a testcase for this scenario. I had run
regression with that patch, and didn't catch any failures and crashes.
-- 
Best Wishes,
Ashutosh Bapat
EnterpriseDB Corporation
The Postgres Database Company