Variable Constraint Messages: Example 4

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.