Variable Constraint Messages: Example 3
In the Travel Agency, the business rule: "The return date of a scheduled tour must match the preset duration of the tour" is implemented by a corrective constraint:
UPDATE schedtour st
For this constraint, you may specify the message:
The scheduled tour to <st.destination.value> on <st.start_date.value> ends on <st.return_date.value>.
This will lead to an information message at run-time.