Re: BUG #15245: pg_stat_all_tables does not include partition mastertables

Hello.

On 2018/06/18 22:58, Mahadevan Ramachandran wrote:
> On Mon, Jun 18, 2018 at 3:51 PM, Amit Langote
> <Langote_Amit_f8@lab.ntt.co.jp> wrote:
>> about how to aggregate across partitions.  We could leave that NULL for
>> now, that is, if we decide to list partitioned tables in the
>> pg_stat_all_tables output at all re OP's complaint.
> 
> "Complaint" is too strong a word :-)

Ah, maybe "opinion" would've been more appropriate. ;-)

> I guess the real issue is that both options are a bit inconsistent. Not listing
> a partitoned table in an "all tables" view does not seem any worse or better
> than having it there with all columns as NULL. Should've thought about it
> before I raised the bug :-)

Yeah.

> Might I suggest a new system view that lists all (parent, child) associations,
> which can then be joined with pg_stat_all_tables so users can roll up
> child table stats into each parent using whatever aggregation functions
> they'd like?

I guess that's more or less what Michael mentioned upthread.  That we need
a user-level function(s) that exposes the partition tree structure and
perhaps an accompanying view that makes inspecting the stats, relation
sizes, etc. of the tables in a given partition tree easier.

Thanks,
Amit