Re: serial data type

Steve Haynes wrote:
>

 People seem to be mixing row and rowid.
> As a designer and developer, I would never, repeat never ever,
> allow any application I was responsible for to rely on rowid.
> Even if you happened to get away with it in the particular case,
> Oracle would be quite entitled to change the behavoir, although
> *I believe* current policy is to allow backward compatibilty for
> one major release. In my opinion: Don't rely on it, don't do it. No!
> From a DB purist point of view, rowid isn't there anyway, its just
> a vendor feature. (That should start something...) ;-)
> Steve
> --
> "The floggings will continue until morale improves."

Take a look at the definition of ROWID in the Oracle SQL Language Reference Manual. The ROWID is constant for the life of the row. Now you just need to know what the life of the row is. It can certainly change if the table is exported and imported, or if the table is copied. I suppose there are other situations as well. There are proper uses for ROWID, but you ought to understand them before using it. Also beware of situations involving gateways. Your application may not know where its data comes from, and not all gateways support ROWID. Even if you aren't using a gateway now, you might in the future.

In my (old) copy of the SQL Language manual the format of the ROWID data is defined. I think it was a mistake to do that. We should NEVER allow customers to become dependent on the underlying structure, and the only way to be sure of that is to hide it. I hope we eliminate that ability in the future.

-- 
Stuart Feigin
Oracle Corp., Ret.
Truckee, CA USA


Nothing I say represents the revealed wisdom of Oracle Corporation.
Larry does that.