Re: Partition-wise join for join between (declaratively) partitioned tables

On 2017/09/05 13:20, Amit Langote wrote:
> On 2017/09/04 21:32, Ashutosh Bapat wrote:

>> +1. Will Fujita-san's patch also handle getting rid of partitioned_rels list?
>
> As Fujita-san mentioned, his patch won't. Actually, I suppose he didn't
> say that partitioned_rels itself is useless, just that its particular
> usage in ExecInitModifyTable is.

That's right. (I thought there would probably be no need to create that
list if we created AppendRelInfos even for partitioned partitions.)

> We still need that list for planner to
> tell the executor that there are some RT entries the latter would need to
> lock before executing a given plan. Without that dedicated list, the
> executor cannot know at all that certain tables in the partition tree
> (viz. the partitioned ones) need to be locked. I mentioned the reason -
> (Merge)Append.subplans, ModifyTable.resultRelations does not contain
> respective entries corresponding to the partitioned tables, and
> traditionally, the executor looks at those lists to figure out the tables
> to lock.

I think so too.

Best regards,
Etsuro Fujita