Re: A Normalization Question

> I looked at your example and ... pictures ... means nothing.

In general, the tree shows things and relationship between things. For example the simplified/incomplete example below represents: An instance of thing is person. An instance of person is john. john likes mary. mary's age is 34yr. 34yr's class/type is duration. 34yr's quantity is 34. 34yr's unit is yr. etc.

thing

   inst: person

         inst: mary   (this would expand same as mary below)
         inst: john
               like: mary
                     age: 34 yr
                          cls: duration
                          qty: 34
                          unit: yr

> I have not seen the script you used to create the database.

The qty 1 example was created via XDb2's GUI as the NLI is under development. www.xdb2.com/Example/Ex001.asp shows how to enter some simple things using the GUI and NLI. The NLI looks like below:

create *john cls person. // This create a new thing named john and

                          // classifies it as a person.

// Below is a more verbose method of doing the above

create *.                 // Creates a new thing
create * cls person.      // Relates new thing's cls to person
create * name 'john'.     // Relates new thing's name to string 'john'
                          // Note: creates str 'john', if necessary

// Below is a more verbose method of creating a string

create *.
create * cls string.
create * part1 'j'       // Relate * to one and only symbol j in db
create * part2 'o'       // Relate * to one and only symbol o in db
create * part3 'h'       // Relate * to one and only symbol h in db
create * part4 'n'       // Relate * to one and only symbol n in db

> I wonder what actions are necessary to add 100 boxes to the database.
> I wonder if you can do math with those quantities. For example could
> one ask for the total weight of all boxes ? Or for total cost?

I will post an example.

> I wonder how the Xdb solution compare with an SQL solution.

RM/SQL are robust tools for production environments. XDb2 is a prototype of an experimental data model. For many common applications, RM/SQL solution will be more efficient, but there exists some AI-type apps where XDb2 could do well. Received on Tue Jul 27 2004 - 07:30:09 CEST