Oracle Mid Term
Oracle Mid Term
Oracle Mid Term
The crows feet (many ends) can point whichever way is the easiest
to draw
You must ensure you have all the entities on one single, big
diagram, even if you have hundreds
Correct
4. There is no point in trying to group your entities together on
your diagram according to volume.
Making a diagram pretty is a waste of time. True or False? Mark for
Review
(1) Points
True
False (*)
Incorrect. Refer to Section 10 Lesson 1.
Section 9
(Answer all questions in this section)
5. Which of the following is a logical constraint that could result
from considering how time impacts
an example of data storage? Mark for Review
(1) Points
An ASSIGNMENT may only refer to an EMPLOYEE with a valid employee
record at the Start Date of the ASSIGNMENT. (*)
EMPLOYEE periods can overlap causing the database to crash.
End Date must be before the Start Date.
Dates must be stored with Time.
Correct
6. 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
Mark for
True (*)
False
Correct
8. When you add the concept of time to your data model, your model
becomes more complex. True or False? Mark for Review
(1) Points
True (*)
False
Correct
9. Which of the following would be a logical constraint when
modeling time for a City entity? Mark for Review
(1) Points
People are born in the city and people die in the city.
Cites may change their name and/or which country they are placed
in, if the borders of a country change. (*)
If you are doing a system for any French City, you would need
security clearance.
You need a constant record of cities because they are still
cities, even if leadership changes over time, e.g.
they get a new Mayor.
Incorrect. Refer to Section 9 Lesson 1.
Section 6
(Answer all questions in this section)
10. The first UID for an entity is called the Primary UID, the
second is called Secondary UID and so on.
Mark for Review
(1) Points
Yes, this is the way UID's are named. (*)
No, it is not possible to have more than one UID for an Entity.
Yes, but then it stops. No entities can have more than two UID's.
No, each Entity can only have one UID, the secondary one.
Correct
Page 1 of 5
Section 10
(Answer all questions in this section)
1. A datamodel containing generic modeling techniques must not be
mixed in with non-generic models. The generic entities MUST be drawn
on a diagram of their own. True or False? Mark for Review
(1) Points
True
False (*)
Incorrect. Refer to Section 10 Lesson 2.
2. Generic models are generally far more complex than a specific
model. True or False? Mark for Review
(1) Points
True
False (*)
Incorrect. Refer to Section 10 Lesson 2.
3. Which of the following statements are true for ERD's to enhance
their readability. (Choose Two) Mark for Review
(1) Points
(Choose all correct answers)
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. (*)
Try to avoid crossing lines (*)
The crows feet (many ends) can point whichever way is the easiest
to draw
You must ensure you have all the entities on one single, big
diagram, even if you have hundreds
Correct
Section 9
(Answer all questions in this section)
5. Which of the following is a logical constraint that could result
from considering how time impacts an example of data storage? Mark
for Review
(1) Points
An ASSIGNMENT may only refer to an EMPLOYEE with a valid employee
record at the Start Date of the ASSIGNMENT. (*)
EMPLOYEE periods can overlap causing the database to crash.
End Date must be before the Start Date.
Dates must be stored with Time.
Correct
6. 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? Mark for Review
(1) Points
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. (*)
Email current price to all employees whenever the prices change.
Update the prices in the system, print out the current prices when
they change and pin them on the company noticeboard
Mark for
True (*)
False
Correct
8. When you add the concept of time to your data model, your model
becomes more complex. True or False? Mark for Review
(1) Points
True (*)
False
Correct
9. Which of the following would be a logical constraint when
modeling time for a City entity? Mark for Review
(1) Points
People are born in the city and people die in the city.
Cites may change their name and/or which country they are placed
in, if the borders of a country change. (*)
If you are doing a system for any French City, you would need
security clearance.
You need a constant record of cities because they are still
cities, even if leadership changes over time, e.g. they get a new
Mayor.
Incorrect. Refer to Section 9 Lesson 1.
Section 6
(Answer all questions in this section)
10. The first UID for an entity is called the Primary UID, the
second is called Secondary UID and so on. Mark for Review
(1) Points
Yes, this is the way UID's are named. (*)
No, it is not possible to have more than one UID for an Entity.
Yes, but then it stops. No entities can have more than two UID's.
No, each Entity can only have one UID, the secondary one.
Correct
Page 1 of 5
Test: Mid Term Exam Semester 1
Correct
12. An entity without repeated values is said to be on 1st Normal
Form. True or False? Mark for Review
(1) Points
True (*)
False
Correct
13. Normalizing an Entity to 1st Normal Form is done by removing
repeated or redundant attributes. True or False? Mark for Review
(1) Points
True (*)
False
Correct
14. Would it be a good idea to model age as an attribute of
STUDENT? Mark for Review
(1) Points
Yes
Maybe it could stop us having to calculate someone's age every
time we need it
Sometimes
No - it breaks the Normalization rules (*)
Incorrect. Refer to Section 6 Lesson 3.
15. Any Non-UID must be dependant on the entire UID. True or False?
Mark for Review
(1) Points
True (*)
False
Correct
16. No commercial database systems in the world will accept tables
that are not on 3rd Normal Form. True or False? Mark for Review
(1) Points
True
False (*)
Incorrect. Refer to Section 6 Lesson 4.
Section 5
(Answer all questions in this section)
17. What do you call the entity created when you resolve a M:M
relationship? Mark for Review
(1) Points
Intersection entity (*)
Inclusion entity
Recursive entity
M:M entity
Correct
18. Intersection Entities often have the relationships
participating in the UID, so the relationships are often
barred. True or False? Mark for Review
(1) Points
True (*)
False
Correct
19. When you resolve a M-M you simply re-draw the relationships
between the two original entities,
no new entities are created. True or False? Mark for Review
(1) Points
True
False (*)
Incorrect. Refer to Section 5 Lesson 3.
20. If a relationship can NOT be moved between instances of the
entities it connects, it is said to be: Mark
\for Review
(1) Points
Mandatory
Optional
Transferrable
Non-Transferrable (*)
Incorrect. Refer to Section 5 Lesson 1.
Page 2 of 5
11. People are not born with "numbers", but a lot of systems assign
student numbers, customer IDs, etc.
A shoe has a color, a size, a style, but may not have a descriptive
"number". So, to be able to uniquely and efficiently identify one
instance of the entity SHOE, a/an ______________ UID can be created.
Mark for Review
(1) Points
Artificial (*)
Unrealistic
Structured
Identification
Correct
12. An entity without repeated values is said to be on 1st Normal
Form. True or False? Mark for Review
(1) Points
True (*)
False
Correct
13. Normalizing an Entity to 1st Normal Form is done by removing
repeated or redundant attributes. True or False? Mark for Review
(1) Points
True (*)
False
Correct
14. Would it be a good idea to model age as an attribute of
STUDENT? Mark for Review
(1) Points
Yes
Section 5
(Answer all questions in this section)
17. What do you call the entity created when you resolve a M:M
relationship? Mark for Review
(1) Points
Intersection entity (*)
Inclusion entity
Recursive entity
M:M entity
Correct
18. Intersection Entities often have the relationships
participating in the UID, so the relationships are
often barred. True or False? Mark for Review
(1) Points
True (*)
False
Correct
19. When you resolve a M-M you simply re-draw the relationships
between the two original entities, no new entities are created. True
or False? Mark for Review
(1) Points
True
False (*)
Incorrect. Refer to Section 5 Lesson 3.
20. If a relationship can NOT be moved between instances of the
entities it connects, it is said to be: Mark for Review
(1) Points
Mandatory
Optional
Transferrable
Non-Transferrable (*)
Incorrect. Refer to Section 5 Lesson 1.
Page 2 of 5
Correct
14. Would it be a good idea to model age as an attribute of
STUDENT? Mark for Review
(1) Points
Yes
Maybe it could stop us having to calculate someone's age every
time we need it
Sometimes
No - it breaks the Normalization rules (*)
Incorrect. Refer to Section 6 Lesson 3.
15. Any Non-UID must be dependant on the entire UID. True or False?
Mark for Review
(1) Points
True (*)
False
Correct
16. No commercial database systems in the world will accept tables
that are not on 3rd Normal Form. True or False? Mark for Review
(1) Points
True
False (*)
Incorrect. Refer to Section 6 Lesson 4.
Section 5
(Answer all questions in this section)
17. What do you call the entity created when you resolve a M:M
relationship? Mark for Review
(1) Points
Intersection entity (*)
Inclusion entity
Recursive entity
M:M entity
Correct
18. Intersection Entities often have the relationships
participating in the UID, so the relationships are often barred. True
or False? Mark for Review
(1) Points
True (*)
False
Correct
19. When you resolve a M-M you simply re-draw the relationships
between the two original entities,
no new entities are created. True or False? Mark for Review
(1) Points
True
False (*)
Incorrect. Refer to Section 5 Lesson 3.
20. If a relationship can NOT be moved between instances of the
entities it connects, it is said to be: Mark for Review
(1) Points
Mandatory
Optional
Transferrable
Non-Transferrable (*)
Incorrect. Refer to Section 5 Lesson 1.
Page 2 of 5
True (*)
False
Correct
Section 4
(Answer all questions in this section)
25. The "Other" subtype is mandatory. True or False?
Review
(1) Points
True
False (*)
Mark for
Section 7
(Answer all questions in this section)
30. A relationship can be both Recursive and Hierachal at the same
time. True or False? Mark for Review
(1) Points
True
False (*)
Incorrect. Refer to Section 7 Lesson 2.
Page 3 of 5
Mark for
True
False (*)
Incorrect. Refer to Section 7 Lesson 1.
37. Historical data must never be kept. True or False?
Review
(1) Points
Mark for
True
False (*)
Incorrect. Refer to Section 7 Lesson 3.
38. Modeling historical data can produce a unique identifier that
always excludes dates. True or False? Mark for Review
(1) Points
True
False (*)
Incorrect. Refer to Section 7 Lesson 3.
Section 3
(Answer all questions in this section)
39. To identify an attribute as part of a unique identifier on an
ER diagram, the # symbol goes in front of it. True or False? Mark for
Review
(1) Points
True (*)
False
Correct
40. Matrix Diagrams are used to verify an ERD. True or False?
for Review
(1) Points
Mark
True (*)
False
Correct
Page 4 of 5
41. Two entities can ONLY have one relationship between them. True
or False? Mark for Review
(1) Points
True
False (*)
Incorrect. Refer to Section 3 Lesson 3.
42. Relationship Names are optional. True or False?
Review
(1) Points
Mark for
True
False (*)
Incorrect. Refer to Section 3 Lesson 1.
43. One Relationship can be both mandatory and optional at
different ends. True or False? Mark for Review
(1) Points
True (*)
False
Correct
Section 2
(Answer all questions in this section)
44. Entity and Attribute names are usually Nouns. True or False?
Mark for Review
(1) Points
True (*)
False
Correct
Mark for
True (*)
False
Correct
47. Which of the following entities most likely contains valid
attributes? (Choose two) Mark for Review
(1) Points
(Choose all correct answers)
Entity: Home. Attributes: Number of Bedrooms, Owner, Address, Date
Built (*)
Entity: Pet. Attributes: Name, Birthdate, Owner (*)
Entity: Car. Attributes: Owner Occupation, Owner Salary, Speed
Entity: Mother. Attributes: Name, Birthdate, Occupation, Salary
Correct
Page 5 of 5