Microsoft Office Tutorials and References
In Depth Information
FIguRE 5-11 Using views, the data model for products is very simple.
You can appreciate several interesting aspects in this structure:
■ When no category or subcategory exists, the view returns a default value for it, indicating
the lack of a value. That default value begins with an open angle bracket so that this
element shows up first in a sorted list, to make it more evident in any report.
■ The same technique has been applied to the color.
■ The view contains the complexity of details about the relationships between products,
subcategories, categories, and product models; the view shows a data model that
already contains denormalized information as attributes of the product table.
■ The FinishedGoodFlag Boolean value has been converted by the view into a more
user-friendly textual description, which is easier to query and analyze.
As you might notice, the view carries on for us the hard task of denormalization and detection
of empty values, along with the handling of relationships.
If you are familiar with SQL, you can see that the SQL query that creates this structure is an
easy one and creating it takes just minutes. If you are not, it is enough to understand that
your IT people will be more than happy to write these queries for you and expose them as
views so that you can easily load data from the database and perform the complex analysis
you want to, without ever asking them to produce any software.