Consider the representation of a ternary relationship using binary relationships as described in Section 7.7.3 and illustrated in Figure 7.27b (attributes not shown).
a. Show a simple instance of E, A, B,C, RA, RB, and RC that cannot correspond to any instance of A, B,C, and R.
b. Modify the E-R diagram of Figure 7.27b to introduce constraints that will guarantee that any instance of E, A, B,C, RA, RB, and RC that satisfies the constraints will correspond to an instance of A, B,C, and R. c. Modify the translation above to handle total participation constraints on the ternary relationship.
d. The above representation requires that we create a primary-key attribute for E. Show how to treat E as a weak entity set so that a primary-key attribute is not required.
