Re: BUG #16619: Amcheck detects corruption in hstore' btree index (ver 2)

On Wed, Sep 16, 2020 at 7:24 AM Anastasia Lubennikova
<a.lubennikova@postgrespro.ru> wrote:
> For v2 indexes pivot tuple's offset can contain any random number which
> will lead to bt_pivot_tuple_identical() failure.
>
> The fix is pretty simple - only compare data part of the tuples. I think
> we can skip offnum check for all index versions to keep the code simple.

I pushed a tweaked version of this patch. It seemed worth preserving
the inclusion of offset number in the bt_pivot_tuple_identical()
memcmp() comparison. The field contains important metadata that really
should match. Also, I made sure to compare t_info field on all indexes
(including pg_upgrade'd indexes) for the same reason.

We already account for heapkeyspace difference in other similar
routines, such as invariant_l_offset().  It's not hard to do this here
as well.

Thanks
-- 
Peter Geoghegan