1.Write SQL statements to create the corresponding relations to the ER diagram you designed for Exercise 2.8. If your translation cannot capture any constraints in the ER diagram, explain why.
2.Consider the following schema:
Suppliers(sid: integer, sname: string, address: string) Parts(pid: integer, pname: string, color: string) Catalog(sid: integer, pid: integer, cost: real)
The Catalog relation lists the prices charged for parts by Suppliers. Answer the fol-lowing questions:
Give an example of an updatable view involving one relation.
Give an example of an updatable view involving two relations.
Give an example of an insertable-into view that is updatable.
Give an example of an insertable-into view that is not updatable.
3.Given two relations R1 and R2, where R1 contains N1 tuples, R2 con-tains N2 tuples, and N2 > N1 > 0, give the minimum and maximum possible sizes (in tuples) for the resulting relation produced by each of the following relational algebra expressions. In each case, state any assumptions about the schemas for R1 and R2 needed to make the expression meaningful:
(1) R1∪R2, (2) R1∩R2, (3) R1−R2, (4) R1×R2, (5) σa=5(R1), (6) πa(R1), and (7) R1/R2