Re: pgsql: New files for MERGE

On Wed, Apr 4, 2018 at 12:09 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Personally, I didn't think we had consensus on whether the semantics
> are right, let alone on whether this is a satisfactory implementation
> code-wise. I know I've never looked at the patch before today; I did not
> think it was close enough to being committed that I would need to.

To be fair, I was happy with the semantics we came up with for READ
COMMITTED conflict handling, although it wasn't that long ago that
that ceased to be the big concern. This happened due to a truly heroic
effort from Pavan.

The problems that remained were with the representation used during
parsing, planning, and execution, which seem like they could have a
lot of unforeseen consequences. Plus a general lack of maturity.
Things like column-level privileges were broken as recently as a week
before commit, due to being totally untested. That was a consequence
of the representation in the executor.

--
Peter Geoghegan