A principal problem with the use of integrity constraints for monitoring the
integrity of a dynamically changing database is their cost of evaluation. This
cost which is associated with the performance of the checking mechanisms is
the main quantitative measure which has to be supervised carefully. We have
developed an integrity constraint subsystem for a relational distributed database
(SICSDD) which consists of several techniques that are necessary for efficient
constraint checking, particularly in a distributed environment where data
distribution is transparent to the application domain. In this paper, we will
show how these techniques have effectively reduced the cost of constraint
checking in such a distributed environment
