Analyzing Data › Additional Data Modeling Topics › General Integrity Constraints

General Integrity Constraints

In some cases, certain combinations of attribute values and relationship memberships can be invalid for entities of a given type. Conditions that determine the validity of entities of a given type are named integrity constraints.

A number of kinds of integrity constraint have already been introduced. Optionality conditions for relationship memberships and attributes, cardinality conditions for relationship memberships, permitted values for attributes, and the mutual exclusivity of relationship memberships are all examples of special kinds of integrity constraints. However, these specifications do not exhaustively address all issues that can determine the validity of an entity. To do so, specify a general integrity constraint.

In CA Gen, integrity constraints that are not otherwise addressed are captured as part of a description for an entity type. During activity analysis, ensure that the integrity constraints documented during data analysis are reflected in the process definition.

Two examples of conditions that are addressed by general integrity constraints are:

• Complex permitted values—Certain permitted values of an attribute are valid only when other attributes have specific values, or when specific pairings exist. For example, imagine that for a CUSTOMER to have the Status: Preferred. They must have a Credit Rating of Impeccable and at least one outstanding ORDER. An analyst record this, in the description of the entity type CUSTOMER, as: Status is equal to Preferred is valid when: Credit Rating is equal to Impeccable, and places ORDER.
• Mutually inclusive relationships—One pairing can exist only if another exists. For example, assume that a PRODUCT can only appear on an ORDER ITEM if it is supplied by a SUPPLIER or is made by a DEPARTMENT. An analyst record this condition, in the description of the entity type PRODUCT, as: Invalid when ordered on order item and not supplied by supplier and not made by a department.