a) When all non-UID attributes are dependent upon the
entire UID. (*)
b) When no attritibutes are mutually independant and
fully independent on the primary key.
c) When no attritibutes are mutually independent and
all are fully dependent on the primary key.
d) None of the Above.
2) Any Non-UID must be dependant on the entire UID. True or False?
a) True
b) False
3) As a database designer you do not need to worry about where in the datamodel you store a particular attribute, as long as you get it onto the ERD your job is done. True or False?
a) True
b) False
4) Until all attributes are single-valued, the database model is said to be:
a) Normalized
b) Not Normalized
c) 1st Normal Form
d) 2nd Normal Form
5) An entity without repeated values is said to be on 1st Normal Form. True or False?
a) True
b) False
6) All entities must be given a new artificial UID. True or False?
a) True
b) False
7) A unique identifier must be made up of more than one attribute. True or False?
a) True
b) False
8) There are formal rules for how to draw ERD's, even though they are only guidelines, you should always try to follow them. True or False?
a) True
b) False
9) Which of the following statements are true for ERD's
to enhance their readability. (Choose Two)
(Choose all correct answers)
a) Is is OK to break a big ERD down into subsets of the
overall picture. This way you end up with more than one ERD, that together
documents the entire system.
b) Try to avoid crossing lines
c) The crows feet (many ends) can point whichever way
is the easiest to draw
d) You must ensure you have all the entities on one single,
big diagram, even if you have hundreds
10) All datamodels must be transformed from specific to generic. True or False?
a) True
b) False
11) Generic models are generally far more complex than a specific model. True or False?
a) True
b) False
12) You are doing a data model for a computer sales company, where the price of postage is dependent on what day of the week goods are shipped. So shipping is more expensive if the customer wants a delivery to take place on a Saturday or Sunday. What would be the best way to model this?
a) Use a Delivery Day entity, which holds prices against
week days, and ensure the we also have an attribute for the Requested Delivery
Day in the Order Entity.
b) Email current price to all employees whenever the
prices change.
c) Update the prices in the system, print out the current
prices when they change and pin them on the company notice board
d) Allow them to enter whatever ever delivery charge
they want.
---
Suggested Answers
1) a
2) a
3) b
4) b
5) a
6) b
7) b
8) a
9) a, b
10) b
11) b
12) a
