The next several posts will be about using the Google Base data model as a language for the Semantic Web.

As outlined in this series of posts, Google Base is very flexible in defining new attributes for the database. Unfortunately, new attributes have to be defined in terms only of base data types and the definition of the type is implied, not defined, by the tag name the user assigns. This is overly simplistic, an unnecessary restriction and inflexible.

For example, let's say you want to define a new attribute. Let's say the person to contact. Since there's no "contact" defined in the standard Attribute Types under the current model, this is what you'd add:

    <gc:contact_person type="string">Johnny Chase</gc:contact_person>

("gc" is the "http://base.google.com/cns/1.0" namespace, as defined here.) Let's face it: this is pretty thin gruel. The computer knows that this is a string and -- if you can read English -- humans can infer than that this is a "Contact Person". Google Base is so close and can do so much better.

We propose that Google Base should allow new Attribute Types to be defined based on existing Attribute Types. For example:

    <gc:contact base="person">Johnny Chase</gc:contact>

That is, we've defined a new type called Contact that's based on an existing Attribute Type called "person"^*. Ooooooo ... very nice, very simple, and we've already gained a lot knowledge -- from a computer point of view -- what "Johnny Chase" is all about. And Google Base hasn't lost anything either -- deep down, it knows it's just a string.

^* we know. See the next message.