Re: MERGE SQL Statement for PG11

On 30 October 2017 at 19:55, Stephen Frost <sfrost@snowman.net> wrote:
> * Robert Haas (robertmhaas@gmail.com) wrote:
>> On Sun, Oct 29, 2017 at 1:19 AM, Simon Riggs <simon@2ndquadrant.com> wrote:
>> > Nothing I am proposing blocks later work.
>>
>> That's not really true.  Nobody's going to be happy if MERGE has one
>> behavior in one set of cases and an astonishingly different behavior
>> in another set of cases.  If you adopt a behavior for certain cases
>> that can't be extended to other cases, then you're blocking a
>> general-purpose MERGE.
>>
>> And, indeed, it seems that you're proposing an implementation that
>> adds no new functionality, just syntax compatibility.  Do we really
>> want or need two syntaxes  for the same thing in core?  I kinda think
>> Peter might have the right idea here.  Under his proposal, we'd be
>> getting something that is, in a way, new.
>
> +1.
>
> I don't think MERGE should be radically different from other database
> systems and just syntax sugar over a capability we have.

I've proposed a SQL Standard compliant implementation that would do
much more than be new syntax over what we already have.

So these two claims aren't accurate: "radical difference" and "syntax
sugar over a capability we have".

> Time changes
> many things, but I don't think anything's changed in this from the prior
> discussions about it.

My proposal is new, that is what has changed.

At this stage, general opinions can be misleading.

Hi ho, hi ho.

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