Re: Requirements for update languages?

alfredo_at_nospam_ncs.es (Alfredo Novoa) writes:

> On 08 Nov 2002 15:26:14 +0100, "Jens
> =?iso-8859-15?q?Lechtenb=F6rger?=" <lechtej_at_uni-muenster.de> wrote:
>
> >while there are some criteria to assess relational query
> >languages (adequate, relationally complete, optimizable) I wonder
> >what makes a good update language for a data model.
> >
> >In particular, I wonder about the following points in SQL.
>
> The problems starts here because SQL is not relational.
>

OK. The "relational" before query language is misleading. I wondered about a good update language for the SQL data model.

> >1. I believe that SQL data manipulations are not adequate for
> >bags,
>
> A bag is not a relation and the Relational Model represents data
> in relations and only relations.
>
> Then SQL is not relational and it could be called "bagational" :-)
>
> With bags the view update problem is very diferent, and a lot more
> complex.

Are you sure? Do you have a reference?

Jens Received on Mon Nov 11 2002 - 07:58:50 CET