Re: [Suspect SPAM] Re: pgsql: Add pg_partition_root to displaytop-most parent of a partition

Hi,

On 2019/03/22 12:55, Michael Paquier wrote:
> On Fri, Mar 22, 2019 at 12:26:12AM -0300, Alvaro Herrera wrote:
>> I noticed days ago that if you call pg_partition_root on the topmost
>> partitioned table, the server crashes :-)

I thought we already fixed that last month, but that was pg_partition_tree().

> It's when you think that the thing is actually done that another issue
> pops up.  The attached fixes the issue, I suggest to return the
> top-most parent as result if the input is the top-most parent itself.
> Returning NULL does not make sense as in this case the relation can be
> part of a partition tree.

Thanks for writing the patch.

     /* Fetch the top-most parent */
     ancestors = get_partition_ancestors(relid);

Maybe, the patch should update this comment to say "Fetch the list of
ancestors".

+
+    /*
+     * If the listed partition is already the top-most parent, just
+     * return itself.
+     */

What does "listed partition" mean?  Maybe, you mean "If the input
relation..."?  How about write this as:

If the input relation is itself the top-most parent, just return itself.

Regards,
Amit