Re: MERGE vs REPLACE

Jaime Casanova wrote:
> On 11/16/05, Bruce Momjian <pgman@candle.pha.pa.us> wrote:
> >
> > Interesting approach.  Actually, we could tell the user they have to use
> > BEGIN;LOCK tab before doing MERGE, and throw an error if we don't
> > already have a table lock.
> >
> 
> If the lock will be required, what's the problem in doing it
> internally? without user interaction?

Because first, we are making it visible to the user, and second the lock
is taken out _before_ we actually execute the statement, meaning we
don't have to escalate our locks.

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
359-1001+  If your life is a hard drive,     |  13 Roberts Road +  Christ can be your backup.        |  Newtown Square,
Pennsylvania19073