METHOD TO ELIMINATE AVOIDABLE CHECKING OF INTEGRITY CONSTRAINTS.

Abstract

Integrity constraints on relational databases can be specified using high-level languages. Methods proposed to enforce constraints range from brute force evaluation to more efficient procedures. Whatever the method of evaluation, an integrity subsystem will be more efficient if certain constraints that are not affected by a specific change in the database state can be excluded automatically from the integrity check. We present a method to do this based on certain rules. Logical verification of these rules and algorithms to implement them are discussed. Examples to illustrate advantages of the method are also provided.