Re: [HACKERS] MERGE SQL Statement for PG11

On Mon, Apr 2, 2018 at 10:40 PM, Peter Geoghegan <pg@bowt.ie> wrote:
> On Mon, Apr 2, 2018 at 7:18 PM, Andres Freund <andres@anarazel.de> wrote:
>> I did a scan through this, as I hadn't been able to keep with the thread
>> previously. Sorry if some of the things mentioned here have been
>> discussed previously. I am just reading through the patch in its own
>> order, so please excuse if there's things I remark on that only later
>> fully make sense.
>>
>>
>> later update: TL;DR: I don't think the parser / executor implementation
>> of MERGE is architecturally sound.  I think creating hidden joins during
>> parse-analysis to implement MERGE is a seriously bad idea and it needs
>> to be replaced by a different executor structure.
>
> +1. I continue to have significant misgivings about this. It has many
> consequences that we know about, and likely quite a few more that we
> don't.

+1.  I didn't understand from Peter's earlier comments that we were
doing that, and I agree that it isn't a good design choice.

-- 
Robert Haas
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