On 2015/02/10 14:49, Etsuro Fujita wrote:
> On 2015/02/07 1:09, Tom Lane wrote:
>> IIRC, this code was written at a time when we didn't have NO INHERIT check
>> constraints and so it was impossible for the parent table to get optimized
>> away while leaving children. So the comment in ExplainModifyTarget was
>> good at the time. But it no longer is.
>>
>> I think your basic idea of preserving the original parent table's relid
>> is correct; but instead of doing it like this patch does, I'd be inclined
>> to make ModifyTable inherit from Scan not Plan, and use the scan.scanrelid
>> field to carry the parent RTI. Then you would probably end up with a net
>> savings of code rather than net addition; certainly ExplainModifyTarget
>> would go away entirely since you'd just treat ModifyTable like any other
>> Scan in this part of EXPLAIN.
>
> Will follow your revision.
Done. Attached is an updated version of the patch.
Best regards,
Etsuro Fujita