Re: Do Data Models Need to built on a Mathematical Concept?
Date: 7 May 2003 09:02:35 -0700
> > > But, in the rdb model, that flexibility cannot be
> > > fully realized because the type of values in a domain is restricted to
> > > some hardware dependent type (ie int, long, date, 50 chars, etc).
> > That might be a limitation on, say, Oracle, but it's not a limitation
> > of the relational model. Domains can be anything; the relational
> > model doesn't say anything about them at all, other than to say
> > they are sets of values.
> You are correct, in the rdb model itself, a tuple's values are not
> associated with any data type. Data types only appear in
> implementation of the rdb model.
Clearification, according to the relational model, the values of a domain do have a data type. But here the word data type essentially means domain and has nothing to do with hardware as you had expressed. Received on Wed May 07 2003 - 18:02:35 CEST