This paper presents a decompositional approach to integrity constraint enforcement for very large database systems. The central theme of the paper is the development of the constraint decomposition theorem which can be used to decompose any complex constraint formula into a set of simpler constraint sub-formulas, each of which is a sufficient condition for the original constraint formula and they can be enforced independently of one another. By utilizing the decomposition theorem and the fact that both cost for checking each sub-formula and satisfiability of each sub-formula may be different from one another, we developed a new constraint enforcement strategy which is much efficient than the previous approaches.
