Bruce Momjian wrote:
> I agree --- an implementation that needs to use a table lock is
> useless, and one with no primary key is too hard to implement and
> also near useless.
Well, there were just a couple of people saying the opposite.
> I have update the TODO item to reflect this:
>
> * Add MERGE command that does UPDATE/DELETE, or on failure, INSERT
> (rules, triggers?)
>
> To implement this cleanly requires that the table have a unique
> index so duplicate checking can be easily performed.
We're still trying to work out the semantic relationship between MERGE
and REPLACE and what-we-actually-want. This entry doesn't seem to take
that into account.
--
Peter Eisentraut
http://developer.postgresql.org/~petere/