Data Modeling with the Entity-Relationship Model - Database Processing: Fundamentals, Design, and Implementation - page 224

(a)

Figure 5-59
Cereal Product Reports

(b)

C.

Construct an IE Crow's Foot model showing relationships among your entities. Name
each relationship and specify cardinalities. Indicate which cardinalities you can jus-
tify on the basis of these reports and which you will need to check out with the users.

5.62 Consider the CD cover in Figure 5-60.

a.

Specify identifiers and attributes for the entities CD, ARTIST, ROLE, and SONG.

B.

Construct a crow's foot model showing relationships among these four entities.
Name each relationship and specify cardinalities. Indicate which cardinalities you
can justify on the basis of the CD cover and which you will need to check out with
the users.

C.

Consider a CD that does not involve a musical, so there is no need for ROLE.
However, the entity SONG_WRITER is needed. Create a crow's foot model for CD,
ARTIST, SONG, and SONG_WRITER. Assume that an ARTIST can either be a group
or an individual. Assume that some artists record individually and as part of a group.