Databases Reference
In-Depth Information
Another example of a role-playing dimension might be a school district that
is responsible for educating a student. There is a district, usually where the
student resides, that is legally responsible for educating that student. In some
cases, a student is actually receiving instruction from a different school district,
perhaps for special services or because a parent works for the other district.
Other Notation
The business dimensional model should be easily printed on 8
1
/
2
'' by 11''
paper. By storing the diagrams and tables in a word processing document,
many users can print it without requiring special software. A few additional
notations can be used to make the model easier to read.
Dimension Connectors
If you have a dimension that has too many attributes to fit on a single page,
you can diagram the dimension across multiple pages. The best way to do
this is to include the basic, most important attributes on the main page. Then
use a connector, as shown in Figure 7-23, to link to the other pages. Try to
group the attributes on each page based upon their meaning. For example,
if you are trying to represent a dimension for all the different products that
are purchased by a large enterprise, you might group the attributes by office
supplies, office furniture, and electronic equipment. There would then be a
separate page with the attributes specific to office supplies, office furniture,
and electronic equipment.
1
Product Type
2
Purchase/
Lease
3
Product
Figure 7-23
Dimension connector example
