Re: INSERT ... ON CONFLICT {UPDATE | IGNORE} 2.0

On 02/20/2015 10:39 PM, Peter Geoghegan wrote:
> On Fri, Feb 20, 2015 at 11:34 AM, Heikki Linnakangas
> <hlinnakangas@vmware.com> wrote:
>> So, um, are you agreeing that there is no problem? Or did I misunderstand?
>> If you see a potential issue here, can you explain it as a simple list of
>> steps, please.
>
> Yes. I'm saying that AFAICT, there is no livelock hazard provided
> other sessions must do the pre-check (as they must for ON CONFLICT
> IGNORE). So I continue to believe that they must pre-check, which you
> questioned.
> ...
> Hard to break down the problem into steps, since it isn't a problem
> that I was able to recreate (as a noticeable livelock).

Then I refuse to believe that the livelock hazard exists, without the 
pre-check. If you have a livelock scenario in mind, it really shouldn't 
be that difficult to write down the list of steps.
- Heikki