Consider the Presentation Layer ER diagram.
a. Identify the base and weak entity types. What is (are) the unique identifier(s) of each entity type? Which unique identifiers are composite attributes?
b. Identify the partial key(s).
c. Identify the optional attributes. Which of these are multi-valued attributes?
d. Identify the derived attributes. What is it about these attributes that allows them to be considered "derived" attributes?
e. Identify the recursive and binary relationship types.
f. Which relationship types exhibit (a) total participation of each entity type, (b) partial participation of each entity type, and (c) total participation of one entity type and partial participation of the second entity type?
g. Describe the nature of each relationship type with (a) 1:1 cardinality ratio, (b) a 1:n cardinality ratio, and (c) an m:n cardinality ratio.
h. What is the significance of the use of the double diamond in naming the Goes_for relationship type versus the use of a single diamond to name the Performs relationship type?
i. Describe an obvious business rule that would be associated with the Reserv_dte attribute in the RESERVATION entity type.
j. What does the assignment of the attribute Cost to the Performs relationship type mean?