Question: Referential integrity constraints as defined in this chapter inv

Referential-integrity constraints as defined in this chapter involve exactly two relations. Consider a database that includes the following relations:
salaried-worker (name, office, phone, salary)
hourly-worker (name, hourly-wage)
address (name, street, city)
Suppose that we wish to require that every name that appears in address appear in either salaried-worker or hourly-worker, but not necessarily in both.
a. Propose syntax for expressing such constraints.
b. Discuss the actions that the system must take to enforce a constraint of this form.

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  • CreatedJanuary 28, 2011
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