Re: MERGE issues around inheritance

On Mon, 26 May 2025 at 07:46, Tender Wang <tndrwang@gmail.com> wrote:
>
> Hi Dean,
>
>  "it is possible for the parent to be excluded from the
> plan and so all of the entries in the resultRelInfo array may be for
> different relations than rootResultRelInfo."
>
> I didn't fully understand the above sentence.  Can you give me more information or an example?
> If the parent is excluded from the plan, the first entry in the resultRelInfo array will not be the parent but some
survivingchild.
 

There's an example in the updated regression tests. A non-inherited
CHECK constraint on the parent causes the planner to exclude the
parent from the relations being scanned and from the resultRelInfo
array, so the first resultRelInfo entry is for a child relation.

Regards,
Dean