Section 5 Design
RELATIONSHIP TRANSFERABILITY
If a relationship can be moved between instances of the entities it connects, it is said to be:
Transferrable
A non-transferable relationship is represented by which of the following symbols?
Diamond
Non-transferable relationships can only be mandatory, not optional. True or False?
True
RELATIONSHIP TYPES
Which of the following pairs of entities is most likely to be modeled as a M:M relationship?
STUDENT and CLASS
CAR and DRIVER
When resolving an M:M relationship, the new relationships will always be __________ on the many side.
Mandatory
If the same relationship is represented twice in an Entity Relationship Model, it is said to be:
Redundant
Many to many relationships between entities usually hide what?
Another entity
What
uncommon relationship is described by the statements: "Each LINE must
consist of many POINTS and each POINT must be a part of many LINES"
Many to Many Mandatory
When are relationships unnecessary?
When you can derive the relationship from other relationships in the model
Which of the following are relationship types?
Many to Many
One to Many
RESOLVING MANY-TO-MANY RELATIONSHIPS
Many-to-Many
relationships are perfectly acceptable in a finished ERD. There is no
need to do any more work on them. True or False?
False
If an intersection entity is formed that contains no attributes of its own, its uniqueness may be modeled by
Barring the relationships to the original entities.
When you resolve a M-M by creating an intersection entity, this new entity will always inherit:
A relationship to each entity from the original M-M.
sumur : http://quizoracle.blogspot.co.id/2010/11/section-5-design.html
