Re: dbdebunk 'Quote of Week' comment

x schrieb: 
This means that there must be a one to one mapping between the generated key
and some key with a meaning for the end user. Therefore that meaningless
primary key is a pointer. But one of the goals of the relational model is to
eliminate pointers from the data model.

What is the difference between meaningless and meaningful pointer? I think the model itself does not know anything about the meaning of the pointers/keys it uses. In this sense the question about the meaning of pointers/keys relates to data modeling in general rather than to the RM. In other words, the question is if we should choose meaningful or meaningless identifiers for our entites.

Other goal is to give the end user direct access to data.

Any access is indirect (by definition). By direct access we normally mean some lower level mechanism of access w.r.t. this level. (Absolutely) direct access does not exist just like instant interaction does not exist. Possibly you mean an illusion of direct access like in OOP where we manipulate object like if they were directly accessible.

--
http://conceptoriented.com
.