Mid term Exam Oracle Desain Semester 1 v

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Test: Mid Term Exam Semester 1

Answer the question(s) on this page, and click Next to go to the next test page. Click Summary to see

which questions you need to answer before submitting the test. Click Finish Test if you are ready to

submit your test.

Section 1

(Answer all questions in this section)

1. Businesses involved in any of the following typically use databases to handle their data: Finance, Logistics, Commerce, Procurement, and Distribution? True or False?

Mark for Review (1) Points

True

False

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True

False

3. What is the diference between "information" and "data"? Mark for Review

(1) Points

Data is held and understood only by users.

Information is held and understood only by users.

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Data turns into useful information. It is stored in a database and accessed by systems and users.

4. Databases are used in most countries and by most governments. Life, as we know it, would change drastically if we no longer had access to

databases. True or False? Mark for Review

(1) Points

True

False

Section 2

5. In a physical data model, an entity becomes a/an? Mark for Review

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Experience

Instance

Table

None of the above

6. The entity/relationship model is created before the physical database design model? True or False?

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False

7. All of the following could be attributes of an ENTITY called PERSON, except which one?

Haircolor

Weight

Gender

Natacha Hansen

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(Choose all correct answers)

TRANSPORTATION METHOD: Car

ANIMAL: Dog

MEAT PRODUCT: Lettuce

BODY PART: Larry Ellison

9. An entity can have many Unique Identifers. True or False? Mark for Review

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True

False

10. An ERD is an example of a Physical Model. True or False? Mark for Review

(1) Points

True

False

Test: Mid Term Exam Semester 1

Answer the question(s) on this page, and click Next to go to the next test page. Click Summary to see

which questions you need to answer before submitting the test. Click Finish Test if you are ready to

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Section 2

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11. Entity and Attribute names are always interchangable, so you need not worry about choosing the right type. True or False?

True

False

Section 3

12. In a business that sells pet food, choose the best relationship name between FOOD TYPE and ANIMAL (e.g. dog, horse, or cat). (Choose Two)

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Each FOOD TYPE must be suitable for one or more ANIMALs.

Each ANIMAL must be the seller of one or more FOOD TYPES.

Each FOOD TYPE may be made from one or more ANIMALs.

Each FOOD TYPE may be given to one or more ANIMALs.

13. Which of the following are true about Cardinality? (Choose two) Mark for Review

(1) Points

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Cardinality specifes only singularity or plurality, but not a specifc plural number.

Cardinality specifes a counting number (like 1, 2, 3, 4 etc.) in a relationship.

Cardinality specifes whether something is required or not.

14. Which symbol is used to show that a particular attribute is mandatory? Mark for Review

(1) Points

*

o

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&

15. Matrix Diagrams are developed BEFORE the ERD. True or False? Mark for Review

(1) Points

True

False

16. Matrix Diagrams are mandatory when doing data modelling. True or False?

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False

Section 4

17. A new system would have a mixture of both Procedural and Structural Business Rules as part of the documentation of that new system. True or False?

True

False

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(1) Points

True

False

19. Which of the following are suitable Entity names? (Choose Two) Mark for Review

(1) Points

DOGS

ANIMAL

(14)

DOG

20. All instances of a subtype may be an instance of the supertype but does not have to. True or False?

True

False

Section 4

21. A supertype can only have two subtypes and no more. True or False? Mark for Review

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True

False

22. All instances of the supertype must be an instance of one of the subtypes. True or False?

True

False

Section 5

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two original entities; no new entities are created. True or False? Mark for Review

(1) Points

True

False

24. Intersection Entities are at the Parent end of the newly created 1:M (Parent:Child) relationship; therefore, the original entities are the children of the newly created intersection entity. True or False?

True

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25. 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

26. If a relationship can NOT be moved between instances of the entities it connects, it is said to be:

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Optional

Transferable

Non Transferable

27. What uncommon relationship is described by the statements: "Each DNA SAMPLE may be taken from one and only one PERSON and each PERSON may provide one and only one DNA SAMPLE"

One to Many Optional

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One to One Optional

Many to Many Mandatory

28. Many to many relationships must be left in the Model. It is important to have them documented as M:M. True or False?

True

False

29. Which of the following pairs of entities is most likely to be modeled as a M:M relationship?

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(1) Points

CAR and WHEEL

TREE and BRANCH

PERSON and FINGERPRINT

TEACHER and SUBJECT AREA

30. If two entities have two relationships between them, these relationships can be either _____________ or _____________ .

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Replicated or Required

Resourced and Really Good

Redundant and Replicated

Section 6

31. When is an entity in 2nd Normal Form? Mark for Review

(1) Points

When all non UID attributes are dependent upon the entire UID.

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When no attritibutes are mutually independent and all are fully dependent on the primary key.

None of the Above.

32. No commercial database systems in the world will accept tables that are not on 3rd Normal Form. True or False?

True

False

33. An entity without repeated values is said to be in 1st Normal Form. True or False?

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True

False

34. A unique identifer must be made up of more than one attribute. True or False?

True

False

35. People are not born with "numbers", but a lot of systems assign student numbers, customer IDs, etc. ﾠA shoe has a color, a size, a style, but may not have a descriptive "number". So, to be able to uniquely and efciently

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created.

Artifcial

Unrealistic

Structured

Identifcation

Section 7

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BABY and AGE

CUSTOMER and PAYMENTS

TEACHER and AGE

CUSTOMER and ORDERS

37. A single relationship can be both Recursive and Hierarchical at the same time. True or False?

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True

False

38. Arcs are used to visually represent _________ between two or more relationships in an ERD.

Sameness

Diferences

Exclusivity

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39. Arcs are Mandatory in Data modeling. All ERD's must have at least one Arc. True or False?

True

False

40. Which of the following is NOT a relationship type? Mark for Review

(1) Points

Some to None

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One to Many

Many to Many

Section 7

41. No parts of an UID are mandatory. True or False? Mark for Review

(1) Points

True

False

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(1) Points

True

False

Section 9

43. Which of the following would be a logical constraint when modeling time for a City entity?

People are born in the city and people die in the city.

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If you are doing a system for any French City, you would need security clearance.

Daily trafc patterns must be monitored to determine how many law enforcement ofcers are needed.

44. What do users lose when using a system that has no concept of time? Mark for Review

(1) Points

Journalling becomes much easier.

(31)

Tracking data over a period of time becomes impossible.

Nothing is lost if a system does not track time.

45. Which of the following is a logical constraint that could result from considering how time impacts an example of data storage?

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.

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Dates must be stored with Time.

46. You are doing a data model for a computer sales company where the price of postage depends upon the day of the week that 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?

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 prices to all employees whenever a price changes.

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Allow them to enter whatever delivery charge they want.

Section 10

47. Which of the following statements are true for ERD's to enhance their readability. (Choose Two)

It is OK to break down a large ERD into subsets of the overall picture. By doing so, you end up with more than one ERD that, taken together, documents the entire system.

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The crows feet (many ends) can point whichever way is the easiest to draw.

You must ensure that you have every single entity even if hundreds of them exist on one single, big diagram.

48. There is no point in trying to group your entities together on your diagram according to volume, and making a diagram look nice is a waste of time. True or False?

49. All datamodels must be transformed from specifc to generic. True or False? Mark for Review

(35)

True

False

50. Generic models are generally far more complex than a specifc model. True or False?

True