On 2014-09-29 15:16:49 -0700, Kevin Grittner wrote:
> Andres Freund <andres@2ndquadrant.com> wrote:
>
> > Wrong. You can't realistically implement the guarantees of UPSERT
> > without a corresponding UNIQUE index.
>
> You definitely can do it; the question is what you consider
> reasonable in terms of development effort, performance, and
> concurrency.
Right. You can exclusively lock the table and such. The point is just
that nobody wants that. I.e. people want to be warned about it.
> I think the problem can be solved with non-scary values of pretty much
> any two of those. I guess my assumption is that we won't handle the
> general case until someone wants to put the substantial development
> effort into making the other two acceptable.
Which would be a major loss because MERGE is rather useful outside of
atomic upsert.
Greetings,
Andres Freund
-- Andres Freund http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
Services
