An approach to automatic maintenance of semantic integrity in large design data bases

One way a data base can cease retaining a meaningful relationship with the "real world" situation that it models is through violations of its semantic integrity , i.e., transgressions of the defining constraints of its data. These constraints state the legality of the data values and are defined by the creators of the data, e.g., a checking account cannot be negative, or the salary of an assistant professor cannot be greater than that of a full professor.