Re: ToDo: show size of partitioned table

Hi Mathias, Pavel,

On 2018/08/17 12:26, Mathias Brossard wrote:
> On Thu, Aug 16, 2018 at 12:46 AM Pavel Stehule <pavel.stehule@gmail.com>
>>
>> This is question - maybe we can support older partitioning based on only
>> inheritance - and the query can be more exact on PostgreSQL 10 and newer.
>>
>> Please, send any patch. You are welcome.
> 
> In my very humble opinion, I would restrict the definition of partitions to
> declarative partitioning. My justification would be that partitions all use
> inheritance, but not all inheritance is a partition (how would you handle
> multiple inheritance).
> 
> See patch attached that fails (in a way similar to other features) when
> connected to servers with version earlier than 10.0.

The patch to add the pg_partition_tree() function was just committed:

Add pg_partition_tree to display information about partitions
https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=d5eec4eefde70

Could one of you please revise the patch to use that function to produce
the output of \dP+?

Note that pg_partition_tree simply scans the underlying catalog to get all
the tables, so if you pass it a table that's not partitioned (relkind ==
'r'), but has inheritance children, the children will be returned in its
output.  So, if you want to limit the output of \dP to partitioned tables,
be sure to include relkind = 'p' condition in the query.

Thanks,
Amit