This chapter opened with a definition of business rules. You learned that a business rule is a constraint imposed on a field or a relationship that is based on the way the organization perceives and uses its data and that it is derived from the manner in which the organization functions or conducts its business. You now know that there are two major types of business rules: database oriented and application oriented. Although our focus here is on database oriented business rules, you know that you can at least record the basic elements of application oriented business rules for use later in the implementation process.
You then learned that database oriented business rules are divided into two categories: field specific business rules, which affect the elements of a field specification for a particular field; and relationship specific business rules, which affect the characteristics of a relationship.
The chapter continued with a discussion of defining and establishing business rules. Here you learned that you work with users and management to define the business rules required by the organization. You also learned that it is best to establish the field specific business rules first, followed by the relationship specific business rules.
Next, you learned the steps necessary to define and establish each type of business rule. You now know that, in general, you work with a field or relationship, review the field or relationship in light of the rule to determine whether any constraints are necessary, define the appropriate business rule, establish the rule by modifying the appropriate field specification elements or relationship characteristics, decide which actions test the rule, and then complete a Business Rule Specifications sheet for the rule.
The chapter continued with a discussion of the elements of the Business Rule Specifications sheet, and how each element on the sheet is defined. As you now know, using Business Rule Specifications sheets allows you to document all of your rules and provides you with a standard method for recording and reviewing them.
We closed the chapter by discussing validation tables. You learned that you can create and use a validation table to support a business rule that limits the range of values for a particular field. In this manner, the validation table helps to enforce data integrity. You also learned that you need to establish new relationships when you use validation tables and that these relationships have the same types of characteristics as any other types of relationships in the database.