Re: someone working to add merge? - Mailing list pgsql-hackers

From Peter Eisentraut
Subject Re: someone working to add merge?
Date
Msg-id 200511181730.36058.peter_e@gmx.net
Whole thread Raw
In response to Re: someone working to add merge?  (Bruce Momjian <pgman@candle.pha.pa.us>)
Responses Re: someone working to add merge?  (Martijn van Oosterhout <kleptog@svana.org>)
Re: someone working to add merge?  (Bruce Momjian <pgman@candle.pha.pa.us>)
List pgsql-hackers
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/


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