Re: [HACKERS] UPDATE of partition key

On 2017/11/23 21:57, Amit Khandekar wrote:
> If we collect the partition keys in expand_partitioned_rtentry(), we
> need to pass the root relation also, so that we can convert the
> partition key attributes to root rel descriptor. And the other thing
> is, may be, we can check beforehand (in expand_inherited_rtentry)
> whether the rootrte's updatedCols is empty, which I think implies that
> it's not an UPDATE operation. If yes, we can just skip collecting the
> partition keys.

Yeah, it seems like a good idea after all to check in
expand_inherited_rtentry() whether the root RTE's updatedCols is non-empty
and if so check if any of the updatedCols are partition keys.  If we find
some, then it will suffice to just set a simple flag in the
PartitionedChildRelInfo that will be created for the root table.  That
should be done *after* we have visited all the tables in the partition
tree including some that might be partitioned and hence will provide their
partition keys.  The following block in expand_inherited_rtentry() looks
like a good spot:
       if (rte->inh && partitioned_child_rels != NIL)       {           PartitionedChildRelInfo *pcinfo;
           pcinfo = makeNode(PartitionedChildRelInfo);

Thanks,
Amit