FOL Modeling of Integrity Constraints (Dependencies)

DEFINITION Integrity constraints (also known as dependencies in the relational model) are domain-specific declarations which indicate the intended meaning of the data stored in a database. They complement the description of the structure of the data (e.g. in the relational model the structure is given by listing the names of tables and the names and types of their attributes). Integrity constraints express properties that must be satisfied by all instances of a database schema that can arise in the intended application domain (e.g. “no two distinct employees may have the same ssn value”, “departments have a single manager”, etc.).