On 2019/05/21 23:55, Bruce Momjian wrote:
> On Sun, May 19, 2019 at 02:26:48AM +1200, David Rowley wrote:
>> Thanks, typing that up. I think it lacks a bit detail about what's
>> actually changed. The change is fairly evident and people can see
>> when it takes effect when they look at EXPLAIN and see that the
>> Append/MergeAppend node is missing. Also, an Append/MergeAppend may
>> exist for inheritance tables and an Append can exist for a simple
>> UNION ALL. Both of those cases can have subplans removed to leave only
>> a single subplan, to which the additional parallel paths will be
>> considered.
>
> This brings up a few points. First, it seems the change affects
> partitioned tables and UNION ALL, which means it probably needs to be
> listed in two sections.
How about putting this only in E.1.3.1.3. Optimizer?
Thanks,
Amit