Re: [HACKERS] MERGE SQL Statement for PG11

On 26 March 2018 at 15:39, Pavan Deolasee <pavan(dot)deolasee(at)gmail(dot)com> wrote:

> Now that ON CONFLICT patch is in, here are rebased patches. The second patch
> is to add support for CTE (thanks Peter).
>
> Apart from rebase, the following things are fixed/improved:
>
> - Added test cases for column level privileges as suggested by Peter. One
> problem got discovered during the process. Since we expand and track source
> relation targetlist, the exiting code was demanding SELECT privileges on all
> attributes, even though MERGE is only referencing a few attributes on which
> the user has privilege. Fixed that by disassociating expansion from the
> actual referencing.

Good catch Peter.

> - Added a test case for RLS where SELECT policy actually hides some rows, as
> suggested by Stephen in the past
>
> - Added check to compare result relation's and merge target relation's OIDs,
> as suggested by Robert. Simon thinks it's not necessary given that we now
> scan catalog using MVCC snapshot. So will leave it to his discretion when he
> takes it up for commit

No problem with adding the test, its quick to compare two Oids.

> - Improved explanation regarding why we need a second RTE for merge target
> relation and general cleanup/improvements in that area

> I think it will be a good idea to send any further patches as add-on patches
> for reviewer/committer's sake. I will do that unless someone disagrees.

+1

So v25 is the "commit candidate" and we can add other patches to it.

Given recent bugfix/changes I don't plan to commit this tomorrow anymore.

--
Simon Riggs http://www.2ndQuadrant.com/
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