Re: Objects and Relations

On Feb 6, 1:01 am, "David BL" <davi..._at_iinet.net.au> wrote:
> On Feb 6, 5:01 am, Kenneth Downs <knode.wants.t..._at_see.sigblock>
> wrote:
>
> > Walt wrote:
>
> > >> > All databases, RM or otherwise, are about record-keeping. That is
> > >> > their purpose.
>
> > >> I presume by "keeping" you mean persistence. By "record" do you mean
> > >> a tuple of a relation? If so I don't agree. An RDB is about "record
> > >> keeping", but not an OODB (used appropriately).
>
> > > I don't think the term "record-keeping" is closely related to the term
> > > "record" as you assert above.
> > > Record-keeping predates electronic computers.
> > Yup. I abandoned this thread as soon as I saw that it was never going to be
> > about down-to-earth ideas.
>
> Down to earth as in "muddy"? :)
>
> Could you please define in more detail what "record keeping" means?
> For example does it include the recording of large amounts of text?
>
> I think your characterisation of database versus programs (record
> keepers versus taxis) has to do with persistent state versus transient
> state, or perhaps disk versus memory+CPU rather than with the
> distinction between relational (state) and OO (state).
>
> I note that systems based on RM provide the means to manipulate the RM
> state. So it doesn't seem quite right to say that RM is about
> passive state and OO is about active state. Remember as well that
> most objects don't host their own threads and therefore are passive
> (meaning they only do things when a thread calls their methods).
>
> I claim that the distinction between OO and relational has a lot to do
> with the question of whether entities are inside or outside the
> abstract computational machine, noting that 1) secondary storage is
> part of the machine so persistence has nothing to do with it, and 2)
> at the system level both relational and OO based approaches are
> "active" so that has nothing to do with it either.

Then it seems that what you are essentially saying here is - OO functions at the conceptual layer, and RM at the logical layer. This is not really breaking news... Received on Tue Feb 06 2007 - 02:19:01 CET