Re: dbdebunk 'Quote of Week' comment

David Cressey wrote:
> "Marshall Spight" <marshall.spight_at_gmail.com> wrote in message
> > > If we were to delete the row, and then
> > > insert another row with a different key, who is to say that the system
> > > didn't reuse the unused row?
> >
> > I use the term "row" as a logical term, not a physical one.
>
> I'm not following you. I *think* I use the term "row" as a logical one as
> well.

I think we're almost entirely in agreement here. I just thought the idea of "reus[ing] the unused row" was really only an issue at the physical level.

> > > In practice, this is only partly true. If the DBMS alters either the
> > > content or the location of a row, it may have to do some index
> maintenance
> > > to reflect that change. But at least a row is unpinned except for the
> pins
> > > in the index.
> >
> > I think I'd just change this a tiny bit to say "In the implementation,
> > this is only partly true."
>
> Agreed, with one more tiny change: "In current implementations, this is
> only partly true"

Perfect!

Marshall Received on Sat Aug 27 2005 - 08:50:30 CEST