
This concludes the examination of the rule type Check for Duplicate Records.
The next rule type that will be considered is for the kind of referential integrity that
controls dependent records in child tables.
Referential Integrity for Dependent Records
Relational databases contain tables that are related to each other. Changes in the
primary key of a parent record will affect dependent, or child, records in other tables.
Figure 17.5 provides an example.
In Figure 17.5 a record in the Investment table may contain a record for which
child records exist in the Investor Monthly Distribution, Investor Position, and
Investment Income tables. For instance, ...