In relational data base systems, users access shared data base under the assumption that data base satisfies certain consistency constraints which must be self-consistent.
This thesis studies interrelation constraints which provides the basis for interrelation consistency between data items in different relations and crude classification of the constraints to facilitate the construction of these constraints.
It also studies the method of constructing constraints by introducing the concept of the identity-relationship.
The enforcement mechanisms of the constraints which is necessary to maintain the consistency of data base are suggested.
