Re: Re: new patch of MERGE (merge_204) & a question about duplicated ctid

David Fetter wrote:
> How about implementing an UPSERT command as "take the lock, do the
> merge?" That way, we'd have both the simplicity for the simpler cases
> and a way to relax consistency guarantees for those who would like to
> do so.
>

Main argument against is that path leads to a permanent non-standard
wart to support forever, just to work around what should be a short-term
problem. And I'm not sure whether reducing the goals to only this
actually improves the ability to ship something in the near term too
much. Many of the hard problems people are bothered by don't go away,
it just makes deciding which side of the speed/complexity trade-off
you're more interested in becomes more obvious. What I've been
advocating is making that decision go away altogether by only worrying
about the simple to use and slow path for now, but that's a highly
debatable viewpoint I appreciate the resistence to, if it's possible to
do at all.

--
Greg Smith 2ndQuadrant US greg(at)2ndQuadrant(dot)com Baltimore, MD
PostgreSQL Training, Services and Support www.2ndQuadrant.us
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