Variable Constraint Messages: Example 4
For transitional constraints, you may want to refer to the old values:
SELECT p.first_name, p.last_name, OLD(p.discount) old_discount
FROM person p
WHERE discount > old(discount) + 5
For this constraint, you can specify the message:
The personal discount for <p.first_name.value> <p.last_name.value> currently is <old_discount.value> %.
This percentage must not increase by more than 5% at a time.