Re: Re: REPLACE INTO table a la mySQL

Alex Pilosov wrote:
>
> On Mon, 11 Jun 2001, mlw wrote:
>
> > > Adding another trigger event type will break every existing
> > > DB schema that relies on custom triggers to ensure logical
> > > data integrity. Thus it is unacceptable as solution to
> > > support a non-standard feature - period.
> > >
> > > The question "does this row exist" can only be answered by
> > > looking at the primary key. Now BEFORE triggers are allowed
> > > to alter the key attributes, so the final primary key isn't
> > > known before they are executed.
> > >
> > > Thus the DELETE then INSERT semantic might be the only way.
> > > Pretty havy restriction, making the entire REPLACE INTO
> > > somewhat useless IMHO.
> >
> > The only issue I have with your conclusion about DB schema is that
> > REPLACE is not part of standard SQL, so we do not need be too
> > concerned. Just give them a REPLACE trigger and be done with it. If
> > that isn't good enough, in the FAQ, say that the standard way is
> > insert or update.
> I am not sure I like this: it is possible that someone's security is based
> on triggers, and adding replace as a trigger will let them get around
> it...

BTW, does current LOAD INTO trigger INSERT triggers ?

>Possibly this could be controlled by serverwide option
> 'enable_replace_into' or something like that for people with such setup..?
>
> -alex
>
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