Re: [HACKERS] MERGE SQL Statement for PG11

On 23 March 2018 at 11:26, Pavan Deolasee <pavan(dot)deolasee(at)gmail(dot)com> wrote:
>
>
> On Fri, Mar 23, 2018 at 6:45 AM, Peter Geoghegan <pg(at)bowt(dot)ie> wrote:
>>
>> On Thu, Mar 22, 2018 at 6:02 PM, Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org>
>> wrote:
>> > Incremental development is a good thing. Trying to do everything in a
>> > single commit is great when time is infinite or even merely very long,
>> > but if you run out of it, which I'm sure is common, leaving some things
>> > out that can be reasonable implemented in a separate patch is perfectly
>> > acceptable.
>>
>> We're talking about something that took me less than an hour to get
>> working. AFAICT, it's just a matter of tweaking the grammar, and
>> adding a bit of transformWithClause() boilerplate to the start of
>> transformMergeStmt().
>>>
>>>
>>> I quickly implemented CTE support myself (not wCTE support, since
>>> MERGE doesn't use RETURNING), and it wasn't tricky. It seems to work
>>> when I mechanically duplicate the approach taken with other types of
>>> DML statement in the parser. I have written a few tests, and so far it
>>> holds up.

Peter, if you have the code and you consider it important that this
subfeature is in PostgreSQL, why not post the code so we can commit
it?

Why would we repeat what has already been done?

--
Simon Riggs http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services