Re: UPDATE of partition key

On 20 June 2017 at 03:42, Thomas Munro <thomas(dot)munro(at)enterprisedb(dot)com> wrote:
> Just a thought: If I understand correctly this new array of tuple
> conversion maps is the same as mtstate->mt_transition_tupconv_maps in
> my patch transition-tuples-from-child-tables-v11.patch (hopefully soon
> to be committed to close a PG10 open item). In my patch I bounce
> transition tuples from child relations up to the named relation's
> triggers, and in this patch you bounce child tuples up to the named
> relation for rerouting, so the conversion requirement is the same.
> Perhaps we could consider refactoring to build a common struct member
> on demand for the row movement patch at some point in the future if it
> makes the code cleaner.

I agree; thanks for bringing this to my attention. The conversion maps
in my patch and yours do sound like they are exactly same. And even in
case where both update-row-movement and transition tables are playing
together, the same map should serve the purpose of both. I will keep a
watch on your patch, and check how I can adjust my patch so that I
don't have to refactor the mapping.

One difference I see is : in your patch, in ExecModifyTable() we jump
the current map position for each successive subplan, whereas in my
patch, in ExecInsert() we deduce the position of the right map to be
fetched using the position of the current resultRelInfo in the
mtstate->resultRelInfo[] array. I think your way is more consistent
with the existing code.

--
Thanks,
-Amit Khandekar
EnterpriseDB Corporation
The Postgres Database Company