Database Management Systems
Individual Assignment: Entity Relationship Diagram
Due Tuesday, February 17th
Blue Voyage Music (BVM) is an independent music company that records and markets music CDs. BVM sells CDs wholesale to record stores and music clubs, and also does a retail mail order business.
BVM has several artists on its roster. Some of those artists have released more than one CD. Artists receive performance royalties, i.e., a specified amount of money for each individual track sold. Different artists have different royalty rates per song sold.
Customers, whether wholesale or retail, often buy more than one CD at a time. Wholesale customers in particular will also buy more than one copy of a particular CD. Retail customers pay the manufacturer's suggested retail price (called the MSRP or the 'list price'). Wholesale customers pay a different, lower wholesale price.
Read the problem description carefully before starting. I have included some clarifications and suggestions that might help you make some decisions as to how to approach the problem:
1) Artists and Songs: Assume that there is only one artist per an individual song. Artists can release more than one song;
2) CDs: CDs may be by only one artist, or it might be a compilation of songs from different artists. Assume that some songs may be on more than one CD (i.e, on the artist's CD, and also on a compilation);
3) Royalties: Assume that royalties are best tracked by the individual song.
TASK: You are to develop and submit an entity-relationship diagram (ERD) for this case. You should do the following:
a. Draw the UML E-R diagram for this enterprise, including the attributes for each entity;
b. Identify all possible relationships;
c. Identify the connectivity (in other words, the cardinality) for each relationship;
d. Identify the mandatory/optional dependencies (in other words, the optionality) for the relationships;
e. Identify any weak entities;
f. Resolve all M:N relationships.
Also, specify any additional assumptions you made in designing your diagram on a separate sheet.