Star Schema The Complete Reference

CHAPTER 13Type-Specific Stars

The things represented by a dimension table can often be subdivided into categories or types. Sometimes, the attributes you would like to record in the dimension table vary by type. A department store, for example, describes clothing items with a very different set of attributes from electronic items, yet all of them are products. Similarly, businesses often collect very different information about direct customers and corporate customers, or track different kinds of information for different kinds of facilities or locations.

Specialization by type may also extend to the fact table. The facts surrounding an order, for example, may vary depending on whether the order was for merchandise or for a subscription. Tests, ...