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

On 2017/09/02 4:10, Ashutosh Bapat wrote:
> This rebase mainly changes patch 0001, which translates partition
> hierarchy into inheritance hierarchy creating AppendRelInfos and
> RelOptInfos for partitioned partitions. Because of that, it's not
> necessary to record the partitioned partitions in a
> PartitionedChildRelInfos::child_rels. The only RTI that goes in there
> is the RTI of child RTE which is same as the parent RTE except inh
> flag. I tried removing that with a series of changes but it seems that
> following code in ExecInitModifyTable() requires it.
> 1897 /* The root table RT index is at the head of the
> partitioned_rels list */
> 1898 if (node->partitioned_rels)
> 1899 {
> 1900 Index root_rti;
> 1901 Oid root_oid;
> 1902
> 1903 root_rti = linitial_int(node->partitioned_rels);
> 1904 root_oid = getrelid(root_rti, estate->es_range_table);
> 1905 rel = heap_open(root_oid, NoLock); /* locked by InitPlan */
> 1906 }
> 1907 else
> 1908 rel = mtstate->resultRelInfo->ri_RelationDesc;
>
> I don't know whether we could change this code not to use
> PartitionedChildRelInfos::child_rels.
Though I haven't read the patch yet, I think the above code is useless.
And I proposed a patch to clean it up before [1]. I'll add that patch
to the next commitfest.

Best regards,
Etsuro Fujita

[1]
https://www.postgresql.org/message-id/93cf9816-2f7d-0f67-8ed2-4a4e497a6ab8%40lab.ntt.co.jp