Here's a new version. Many of the old complaints have been fixed; particularly, the handling of partitioned tables is now much cleaner and straightforward. Amit Langote helped considerably in getting this part to shape -- thanks for that. Amit also helped correct the EvalPlanQual behavior, which wasn't quite up to snuff.
There are a few things that can still be improved here. For one, I need to clean up the interactions with table AM (and thus heapam.c etc). Secondarily, and I'm now not sure that I really want to do it, is change the representation for executor: instead of creating a fake join between target and source, perhaps we should have just source, and give optimizer a separate query to fetch tuples from target.
What I did do is change how the target table is represented from parse analysis to executor. For example, in the original code, there were two RTEs that represented the target table; that is gone. Now the target table is always just the query's resultRelation. This removes a good number of ugly hacks that had been objected to.
I'll park this in the January commitfest now.
-- Álvaro Herrera Valdivia, Chile — https://www.EnterpriseDB.com/ "Cómo ponemos nuestros dedos en la arcilla del otro. Eso es la amistad; jugar al alfarero y ver qué formas se pueden sacar del otro" (C. Halloway en La Feria de las Tinieblas, R. Bradbury)
Hi,
This is continuation of review.
+ elog(WARNING, "hoping nothing needed here");
the above warning can be dropped.
+ ExprState *mas_whenqual; /* WHEN [NOT] MATCHED AND conditions */
In my earlier comment I suggested changing notMatched to unmatched - I didn't pay attention to the syntax.