7029
For this assignment, you will use, as a starting point, the entity relationship diagrams you created for your Facebook or Twitter account in Homework 1. Your task is to represent Facebook/Twitter accounts with an ER diagram using the UML notation.
Your final ER diagram must include the following elements:
? Entities, attributes, and relationships between entities
? Primary and foreign keys
? Type of each relationships (such as 0…1, 1…1, 1…*, etc)
? Participation and disjoint constraints
? Superclasses and/or subclasses
Refer to Chapters 13, 16, and 17 for examples of these models. Submit your model as an image file.
In a separate file, also submit your answers to the following questions.
For your model. indicate:
1. Strong entities
2. Weak entities
3. One-to-many relationships
4. One-to-one relationships
5. Many-to-many relationships
6. Multi-valued attributes
7. Composite attributes
8. Derived attributes
9. Candidate keys