Re: [HACKERS] UPDATE of partition key

On Sun, Jan 21, 2018 at 1:43 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> Committed with a bunch of mostly-cosmetic revisions.
>
> Buildfarm member skink has been unhappy since this patch went in.
> Running the regression tests under valgrind easily reproduces the
> failure.  Now, I might be wrong about which of the patches committed
> on Friday caused the unhappiness, but the valgrind backtrace sure
> looks like it's to do with partition routing:

Yeah, that must be the fault of this patch.  We assign to
proute->subplan_partition_offsets[update_rri_index] from
update_rri_index = 0 .. num_update_rri, and there's an Assert() at the
bottom of this function that checks this, so probably this is indexing
off the end of the array.  I bet the issue happens when we find all of
the UPDATE result rels while there are still partitions left; then,
subplan_index will be equal to the length of the
proute->subplan_partition_offsets array and we'll be indexing just off
the end.

-- 
Robert Haas
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