Re: 'update returning *' returns 0 columns instead of empty row with 2 columns when (i) no rows updated and (ii) when applied to a partitioned table with sub-partition

On 2019/02/22 13:43, Tom Lane wrote:
> Amit Langote <Langote_Amit_f8(at)lab(dot)ntt(dot)co(dot)jp> writes:
>> Also, I noticed regression test failure having to do with statement
>> triggers not firing, which makes sense, as there's no ModifyTable to
>> invoke them.
>
> Oh! You are right, that's a separate bug. So really we can't have
> this fast-path exit at all, we should produce a ModifyTable node in
> every case.
>
> I'm too tired to work on that anymore today, do you want to run
> with it?

Sure, see attached a patch.

To fix the trigger bug, we'll be putting a minimally valid-looking
ModifyTable node on top of a dummy plan. So, the bug reported on this
thread is taken care of automatically, because ModifyTable plan's
targetlist is already set correctly.

Thanks,
Amit