Database Concepts 8Th Ed By David M. Kroenke - Test Bank

Database Concepts 8Th Ed By David M. Kroenke – Test Bank

 

Instant Download – Complete Test Bank With Answers

 

 

Sample Questions Are Posted Below

 

Database Concepts, 8e (Kroenke)

Chapter 5  Database Design

 

1) The technique for representing E-R relationships in the relational model is dependent on the minimum cardinality.

Answer:  FALSE

Diff: 1           Page Ref: 325

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

2) For a 1:1 relationship, the key of each table should be placed in the other table as the foreign key.

Answer:  TRUE

Diff: 2           Page Ref: 325-327

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

3) Relationships that are 1:1 do not require referential integrity constraints.

Answer:  FALSE

Diff: 2           Page Ref: 326

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

4) In certain circumstances, there may be a preference as to which table in a 1:1 relationship contains the foreign key.

Answer:  TRUE

Diff: 1           Page Ref: 326

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

5) When applied to 1:N relationships, the term “parent” refers to the many side of the relationship since a child may have many parents.

Answer:  FALSE

Diff: 1           Page Ref: 328

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

 

6) To represent a 1:N relationship in the relational model, the key of the entity on the one side of the relationship is placed as a foreign key in the entity on the many side of the relationship.

Answer:  TRUE

Diff: 2           Page Ref: 328

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

7) To represent a 1:N relationship in the relational model, the key of either entity may be placed as a foreign key in the other entity.

Answer:  FALSE

Diff: 2           Page Ref: 328

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

8) In the relational model, many-to-many relationships cannot be directly represented by relations the way 1:1 and 1:N relationships can.

Answer:  TRUE

Diff: 3           Page Ref: 329

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

9) To represent a M:N relationship in the relational model, an intersection table is created to represent the relationship itself.

Answer:  TRUE

Diff: 1           Page Ref: 330

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

10) The key for an intersection table is always the combination of the keys of the parent entities.

Answer:  TRUE

Diff: 2           Page Ref: 330

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

11) Microsoft Access uses the same pure N:M relationships that occur in data modeling.

Answer:  FALSE

Diff: 2           Page Ref: 346

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

 

12) As far as Microsoft Access is concerned, there are no N:M relationships.

Answer:  TRUE

Diff: 1           Page Ref: 346

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

13) As far as Microsoft Access is concerned, there are no 1:N relationships.

Answer:  FALSE

Diff: 1           Page Ref: 346

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

14) By default, Microsoft Access creates 1:1 relationships between tables.

Answer:  FALSE

Diff: 2           Page Ref: 348

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

15) To create a 1:1 relationship in Microsoft Access, the Indexed property of the foreign key column must be set to Yes (No Duplicates).

Answer:  TRUE

Diff: 3           Page Ref: 350

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

16) Which of the following is true when representing a 1:1 binary relationship using the relational model?

1. A) The key of the entity with the highest minimum cardinality must be placed in the other entity as a foreign key.
2. B) The key of each entity must be placed in the other as a foreign key.
3. C) The key of either entity is placed in the other as a foreign key.
4. D) The key of the entity with the most attributes must be placed in the other entity as a foreign key.
5. E) Both entities must have the same primary key.

Answer:  C

Diff: 1           Page Ref: 325-326

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

17) Given the tables

 

TABLE_A (Attribute1, Attribute2, Attribute3)

TABLE_B (Attribute4, Attribute5, Attribute6)

 

as shown in the figure below, which of the following would display the correct placement of foreign keys in the relational model?

 

 

1. A) TABLE_A (Attribute1, Attribute2, Attribute3)

TABLE _B (Attribute4, Attribute5, Attribute6, Attribute1)

1. B) TABLE _A (Attribute1, Attribute2, Attribute3, Attribute4, Attribute5)

TABLE _B (Attribute4, Attribute5, Attribute6)

1. C) TABLE _A (Attribute1, Attribute2, Attribute3, Attribute4)

TABLE _B (Attribute4, Attribute5, Attribute6, Attribute1)

1. D) TABLE _A (Attribute1, Attribute2, Attribute3)

TABLE _B (Attribute4, Attribute5, Attribute6)

1. E) TABLE _A (Attribute1, Attribute2, Attribute3, Attribute6)

TABLE _B (Attribute4, Attribute5, Attribute6)

Answer:  A

Diff: 2           Page Ref: 325-326

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

18) Which of the following is the correct technique for representing a 1:N relationship in the relational model?

1. A) The key of the entity on the one side is placed into the relation for the entity on the many
2. B) The key of the child is placed into the relation of the parent.
3. C) The key of either relation can be placed into the other relation.
4. D) The key of the entity on the many side is placed into the relation for the entity on the one
5. E) An intersection relation is created, and the keys from both parent entities are placed as keys in the intersection relation.

Answer:  A

Diff: 2           Page Ref: 327-329

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

19) Given the tables

 

PRODUCT (ProductID, Description, Cost)

SUPPLIER (SupplierID, ContactName, PhoneNumber)

 

as shown in the figure below, which of the following would represent the correct placement of foreign keys?

 

 

1. A) PRODUCT (ProductID, Description, Cost)

SUPPLIER (SupplierID, ContactName, PhoneNumber)

1. B) PRODUCT (ProductID, Description, Cost)

SUPPLIER (SupplierID, ContactName, PhoneNumber, ProductID)

1. C) PRODUCT (ProductID, Description, Cost, SupplierID)

SUPPLIER (SupplierID, ContactName, PhoneNumber, ProductID)

1. D) PRODUCT (ProductID, Description, Cost, ContactName)

SUPPLIER (SupplierID, ContactName, PhoneNumber)

1. E) PRODUCT (ProductID, Description, Cost, SupplierID)

SUPPLIER (SupplierID, ContactName, PhoneNumber)

Answer:  E

Diff: 2           Page Ref: 327-329

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

 

20) Which of the following is the correct technique for representing a M:N relationship using the relational model?

1. A) An intersection relation is created, and the key of either entity is placed as a key in both the intersection relation and in the other relation.
2. B) An intersection relation is created with a surrogate key, which is placed in each of the parent entities.
3. C) An intersection relation is created, and the keys of both parent entities are placed as a composite key in the intersection relation.
4. D) The key from either relation is placed as a foreign key in the other relation.
5. E) None of the above

Answer:  C

Diff: 2           Page Ref: 329-331

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

21) Given the tables

 

PRODUCT (ProductID, Description, Cost)

SUPPLIER (SupplierID, ContactName, PhoneNumber)

 

as shown in the figure below, which of the following would represent the correct placement of foreign keys?

 

 

1. A) PRODUCT (ProductID, Description, Cost)

SUPPLIER (SupplierID, ContactName, PhoneNumber)

1. B) PRODUCT (ProductID, Description, Cost, SupplierID)

SUPPLIER (SupplierID, ContactName, PhoneNumber, ProductID)

1. C) PRODUCT (ProductID, Description, Cost)

SUPPLIER (SupplierID, ContactName, PhoneNumber)

PRODUCT_SUPPLIER (ProductID, SupplierID, PhoneNumber)

1. D) PRODUCT (ProductID, Description, Cost, SupplierID)

SUPPLIER (SupplierID, ContactName, PhoneNumber)

1. E) PRODUCT (ProductID, Description, Cost)

SUPPLIER (SupplierID, ContactName, PhoneNumber)

PRODUCT_SUPPLIER (ProductID, SupplierID)

Answer:  E

Diff: 3           Page Ref: 329-331

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

 

22) In many-to-many relationships in a relational database design, ________.

1. A) the key of the child is placed as a foreign key into the parent
2. B) the key of the parent is placed as a foreign key into the child
3. C) the keys of both tables are placed in a third table
4. D) the keys of both tables are joined into a composite key
5. E) Both C and D

Answer:  E

Diff: 2           Page Ref: 329-331

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

23) In many-to-many relationships in a relational database design, ________.

1. A) the intersection table is ID-dependent on one of the parents
2. B) the intersection table is ID-dependent on both of the parents
3. C) the minimum cardinality from the intersection table to the parents is always M
4. D) Both A and B
5. E) Both B and C

Answer:  E

Diff: 3           Page Ref: 329-331

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

24) In relational database design, ID-dependent entities are used to ________.

1. A) represent 1:1 relationships
2. B) represent 1:N relationships
3. C) represent N:M relationships
4. D) handle recursive relationships
5. E) eliminate the need for weak entities being converted to tables

Answer:  C

Diff: 3           Page Ref: 330-331

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

 

25) What relationship pattern is illustrated in the following schema?

 

PRODUCT (ProductID, Description)

SUPPLIER (SupplierID, ContactName, PhoneNumber)

PRODUCT_SUPPLIER (ProductID, SupplierID, Cost)

 

ProductID in PRODUCT_SUPPLIER must exist in ProductID in PRODUCT

SupplierID in PRODUCT_SUPPLIER must exist in SupplierID in PRODUCT

1. A) Association relationship
2. B) Intersection relationship
3. C) Recursive relationship
4. D) Strong entity relationship
5. E) Supertype/subtype relationship

Answer:  A

Diff: 2           Page Ref: 333

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

26) What relationship pattern is illustrated in the following schema?

 

VEHICLE (VehicleID, Cost)

CAR (VehicleID, NumberOfSeats)

TRUCK (VehicleID, CargoCapacity)

 

VehicleID in CAR must exist in VehicleID in VEHICLE

VehicleID in TRUCK must exist in VehicleID in VEHICLE

1. A) Association relationship
2. B) Intersection relationship
3. C) Recursive relationship
4. D) Strong entity relationship
5. E) Supertype/subtype relationship

Answer:  E

Diff: 2           Page Ref: 334

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

 

27) Which of the following is not true about representing subtypes in a relational database design?

1. A) One table is created for the supertype and one for each subtype.
2. B) All of the attributes of the supertype are added to the subtype relations.
3. C) The key of the supertype is made the key of the subtypes.
4. D) A subtype and its supertype are representations of the same underlying table.
5. E) An instance of the supertype may be related to one instance each of several subtypes.

Answer:  B

Diff: 2           Page Ref: 334-335

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

28) Microsoft Access does not create N:M relationships because ________.

1. A) Microsoft Access creates databases based on database designs instead of data models.
2. B) Microsoft Access creates databases based on data models instead of database designs.
3. C) Microsoft Access cannot implement association relationships.
4. D) Microsoft Access cannot implement supertype/subtype relationships.
5. E) Microsoft Access cannot implement recursive relationships.

Answer:  A

Diff: 3           Page Ref: 346

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

29) As far as Microsoft Access is concerned, there are no ________.

1. A) 1:1 relationships
2. B) 1:N relationships
3. C) N:1 relationships
4. D) N:M relationships
5. E) recursive relationships

Answer:  D

Diff: 2           Page Ref: 346

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

 

30) By default, when Microsoft Access creates a relationship between two tables, it creates a(n) ________.

1. A) 1:1 relationship
2. B) 1:N relationship
3. C) N:M relationship
4. D) association relationship
5. E) recursive relationship

Answer:  B

Diff: 2           Page Ref: 346

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

31) To create a 1:1 relationship between two tables in Microsoft Access ________.

1. A) the Indexed property of the foreign key column must be set to No
2. B) the Indexed property of the foreign key column must be set to Yes (Duplicates OK)
3. C) the Indexed property of the foreign key column must be set to Yes (No Duplicates)
4. D) the Data Type of the foreign key column must be set to AutoNumber
5. E) the Smart Tag property of the foreign key column must be set to Foreign Key

Answer:  C

Diff: 2           Page Ref: 346-350

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

32) Microsoft Access does not create N:M relationships because Microsoft Access creates databases based on ________.

Answer:  database designs

Diff: 2           Page Ref: 346

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

33) As far as Microsoft Access is concerned, there are no ________.

Answer:  N:M relationships

Diff: 2           Page Ref: 346

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

34) By default, when Microsoft Access creates a relationship between two tables it creates a(n) ________ relationship.

Answer:  1:N

Diff: 2           Page Ref: 346

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

35) To create a 1:1 relationship between two tables in Microsoft Access, the Indexed property of the foreign key column must be set to ________.

Answer:  Yes (No Duplicates)

Diff: 3           Page Ref: 350

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

36) After a 1:1 relationship has been created between two tables in Microsoft Access, the Relationship Type of One-To-One appears in the ________.

Answer:  Edit Relationships dialog box

Diff: 3           Page Ref: 349

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

37) Explain the representation of a one-to-many strong entity relationship in a relational database design.

Answer:  One-to-many relationships are represented by placing the primary key of the table on the one side of the relationship into the table on the many side of the relationship as a foreign key. The term “parent” refers to the table on the one side of a 1:N relationship, and the term “child” refers to the table on the many side of the 1:N relationship. Therefore, the rule for representing a one-to-many relationship can be summarized as “Place the key of the parent table in the child table as a foreign key.”

Diff: 2           Page Ref: 327-329

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

38) Explain the representation of a many-to-many strong entity relationship in a relational database design.

Answer:  Many-to-many relationships cannot be directly represented in a relational database design. Therefore, many-to-many relationships are essentially broken into two one-to-many relationships by creating an intersection table that represents the relationship itself. The intersection table takes its key as a combination of the keys of the two original, or parent, entities. Each of the parent entities has a one-to-many relationship with the intersection table that is represented by placing the keys of the parents into the intersection table.

Diff: 2           Page Ref: 329-331

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

39) What is an association relationship, and how does it differ from an N:M relationship?

Answer:  An association relationship is very similar to an N:M relationship except that the intersection table has attributes of its own. This means that in addition to the foreign key fields linking to the two strong entities, there is at least one additional field in what would otherwise be called the intersection table but is now an association table. For example, the intersection table ENROLLMENT for STUDENT and CLASS showing student enrollment in each class would normally have two columns: StudentID and ClassID. However, we can turn this intersection table into an association table by adding the column Grade, which records each student’s grade in each class.

Diff: 2           Page Ref: 333-334

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

40) How are 1:1, 1:N and N:M relationships handled in Microsoft Access?

Answer:  By default, when Microsoft Access creates a relationship between two tables, it creates a 1:N relationship. N:M relationships are created in Microsoft Access, as in all other DBMS products, as two 1:N relationships linking the two tables (based on the original two entities) through an intersection table. As far as Microsoft Access is concerned, there are no N:M relationships! To create a 1:1 relationship between two tables in Microsoft Access, the Indexed property of the foreign key column in the table containing the foreign key must be set to Yes (No Duplicates) before the relationship is created. With the property set, the relation is automatically created as a 1:1 relationship.

Diff: 2           Page Ref: 346-351

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M binary relationships

Classification:  Concept

 

41) All recursive relationships are 1:1.

Answer:  FALSE

Diff: 2           Page Ref: 334

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M recursive relationships

Classification:  Concept

 

42) Recursive relationships can be represented in the relational model using the same techniques that are used for binary relationships.

Answer:  TRUE

Diff: 2           Page Ref: 334

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M recursive relationships

Classification:  Concept

 

43) What relationship pattern is illustrated in the following schema?

 

EMPLOYEE (EmployeeID, OfficePhone, Manager)

 

Manager in EMPLOYEE must exist in EmployeeID in EMPLOYEE

1. A) Association relationship
2. B) Intersection relationship
3. C) Recursive relationship
4. D) Strong entity relationship
5. E) Supertype/subtype relationship

Answer:  C

Diff: 2           Page Ref: 334-336

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M recursive relationships

Classification:  Concept

 

44) Which of the following is not true of recursive relationships?

1. A) When the recursive relationship is M:N, an intersection table is created.
2. B) The rows of a single table can play two different roles.
3. C) The techniques for representing the tables are the same as for non-recursive relationships except the rows are in the same table.
4. D) Recursive relationships can be 1:1, 1:N, or M:N relationships.
5. E) Even when the relationship is 1:N, a new table must be defined to represent the relationship.

Answer:  E

Diff: 2           Page Ref: 334

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M recursive relationships

Classification:  Concept

 

45) A(n) ________ is a relationship among entities of the same class.

Answer:  recursive relationship

Diff: 2           Page Ref: 334

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M recursive relationships

Classification:  Concept

 

46) How are one-to-one recursive relationships addressed using the relational model?

Answer:  One-to-one recursive relationships are addressed just the same as one-to-one nonrecursive relationships. The only difference is that both of the related entity instances are in the same entity class. The key of either instance is placed in the other instance as a foreign key. In the case of a recursive relationship, this means that a new attribute is added to the entity class with the recursive relationship. For each instance, this new attribute will contain the value of the key attribute of the instance that is related.

Diff: 2           Page Ref: 334-335

AACSB:  Information Technology

Chapter Obj:  Know how to represent 1:1, 1:N, and N:M recursive relationships

Classification:  Concept

47) An example of a join in SQL is the situation where two attributes of two separate tables are compared for equality in a WHERE clause.

Answer:  TRUE

Diff: 3           Page Ref: 326

AACSB:  Information Technology

Chapter Obj:  Learn SQL statements for creating joins over binary and recursive relationships

Classification:  Concept

 

48) If a weak entity is ID-dependent but not existence-dependent, it can be represented using the same techniques as a strong entity.

Answer:  FALSE

Diff: 3           Page Ref: 324

AACSB:  Information Technology

Chapter Obj:  Learn how to represent weak entities with the relational model

Classification:  Concept

 

49) The key of the parent entity becomes part of the key of an ID-dependent entity.

Answer:  TRUE

Diff: 1           Page Ref: 324

AACSB:  Information Technology

Chapter Obj:  Learn how to represent weak entities with the relational model

Classification:  Concept

 

50) Which of the following is true about representing a weak entity with the relational model?

1. A) If the weak entity is existence-dependent, the key of the parent must be part of the key of the weak entity.
2. B) If the strong entity has a minimum cardinality of 1, the key of the weak entity must be part of the strong entity.
3. C) If the weak entity is ID-dependent, the key of the weak entity must be part of the key of the parent entity.
4. D) If the weak entity is ID-dependent, the key of the parent entity must be part of the key of the weak entity.
5. E) If the parent entity is existence-dependent, then the minimum cardinality of the weak entity is zero.

Answer:  D

Diff: 2           Page Ref: 323-324

AACSB:  Information Technology

Chapter Obj:  Learn how to represent weak entities with the relational model

Classification:  Concept

 

 

51) When transforming an E-R data model into a relational database design, the key of the parent entity should be placed as part of the primary key into the child entity ________.

1. A) when the child entity is ID-dependent
2. B) when the child entity is non-ID-dependent
3. C) when the child entity has a 1:1 relationship with the parent entity
4. D) when the child entity has a 1:N relationship with the parent entity
5. E) when the child entity has a recursive relationship with the parent entity

Answer:  A

Diff: 3           Page Ref: 323-324

AACSB:  Information Technology

Chapter Obj:  Learn how to represent weak entities with the relational model

Classification:  Concept

52) For a(n) ________ weak entity, it is necessary to add the key of the parent entity to the weak entity’s relation so that this added attribute becomes part of the weak entity’s key.

Answer:  ID-dependent

Diff: 2           Page Ref: 323-324

AACSB:  Information Technology

Chapter Obj:  Learn how to represent weak entities with the relational model

Classification:  Concept

 

53) Explain the representation of ID-dependent weak entities using the relational model.

Answer:  A weak entity is represented in the relational model similarly to the representation of a strong entity. First, a relation is defined for the entity. Each attribute in the weak entity becomes a column in the relation. The primary key of the strong entity on which the weak entity is ID-dependent is added to the relation and is made a part of the primary key of the weak entity’s relation along with the weak entity’s identifier. Finally, the relation is evaluated according to the normalization criteria, and any necessary design changes are made to normalize the relation.

Diff: 2           Page Ref: 323-324

AACSB:  Information Technology

Chapter Obj:  Learn how to represent weak entities with the relational model

Classification:  Concept

 

54) The first step in representing entities using the relational model is to determine which identifier will be used as the key.

Answer:  FALSE

Diff: 2           Page Ref: 317

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

 

55) An entity needs to be examined according to normalization criteria before creating a table from it in the relational database design.

Answer:  FALSE

Diff: 2           Page Ref: 316-317

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

56) When creating a table in the relational database design from an entity in the extended E-R model, the attributes of the entity become the rows of the table.

Answer:  FALSE

Diff: 1           Page Ref: 317

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

57) By default, the identifier of the entity becomes the foreign key of the corresponding table.

Answer:  FALSE

Diff: 1           Page Ref: 317

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

58) The ideal primary key is short, numeric, and nonchanging.

Answer:  TRUE

Diff: 2           Page Ref: 318

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

59) A surrogate key is appropriate when the primary key of a table contains a lengthy text field.

Answer:  TRUE

Diff: 1           Page Ref: 318

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

60) One of the important properties of an attribute is whether or not it is required.

Answer:  TRUE

Diff: 2           Page Ref: 318

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

 

61) The first step in transforming an extended E-R model into a relational database design is to ________.

1. A) create a table for each relationship
2. B) evaluate the entities against the normalization criteria
3. C) create a table for each entity
4. D) remove any recursive relationships
5. E) document referential integrity constraints

Answer:  C

Diff: 1           Page Ref: 316-317

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

62) Each attribute of an entity becomes a(n) ________ of a table.

1. A) column
2. B) primary key
3. C) foreign key
4. D) alternate key
5. E) either B or D

Answer:  A

Diff: 1           Page Ref: 318

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

63) The identifier of the entity becomes the ________ of the corresponding table.

1. A) primary key
2. B) foreign key
3. C) supertype
4. D) subtype
5. E) either A or B

Answer:  A

Diff: 1           Page Ref: 317

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

 

64) A surrogate key should be considered when ________.

1. A) a relationship is M:N
2. B) a composite key is required
3. C) the key contains a lengthy text field
4. D) the key contains a number
5. E) an index needs to be created

Answer:  C

Diff: 3           Page Ref: 318

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

65) Which of the following is not true about surrogate keys?

1. A) They are identifiers that are supplied by the system, not the users.
2. B) They have no meaning to the users.
3. C) They are nonunique within a table.
4. D) They can be problematic when combining databases.
5. E) The DBMS will not allow their values to be changed.

Answer:  C

Diff: 2           Page Ref: 318

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

66) One of the important properties of a column is whether or not it is ________.

1. A) found in more than one entity
2. B) required
3. C) character or numeric
4. D) subject to normalization
5. E) subject to denormalization

Answer:  B

Diff: 2           Page Ref: 318

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

67) In a relational database design, all relationships are expressed by ________.

1. A) creating a primary key
2. B) creating a foreign key
3. C) creating a supertype
4. D) creating a subtype
5. E) creating a line between entities

Answer:  B

Diff: 1           Page Ref: 317

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

68) After a 1:1 relationship has been created between two tables in Microsoft Access, the Relationship Type of One-To-One appears ________.

1. A) in the Relationship Type property of the primary key column in table Design View
2. B) in the Relationship Type property of the foreign key column in table Design View
3. C) in the table object in the Relationships window
4. D) in the Show Table dialog box
5. E) in the Edit Relationships dialog box

Answer:  E

Diff: 2           Page Ref: 349

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

69) The first step of database design is to define a table for each ________.

Answer:  entity

Diff: 1           Page Ref: 316

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

70) To represent a many-to-many relationship in the relational model, a(n) ________ table is used.

Answer:  intersection

Diff: 1           Page Ref: 330

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

71) Explain the process of representing an entity using the relational model.

Answer:  To represent an entity using the relational model, first define a relation for the entity. The name of the entity is the name of the relation. Each attribute in the entity becomes a column in the relation. If the entity had a unique identifier that would make an appropriate primary key, then that attribute is made the key. If there is no such attribute, then the development team discusses identifiers with the users to determine if an acceptable key attribute exists. If not, then a surrogate key may be used. Finally, the relation is evaluated against the normalization criteria. Changes to the design may be necessary to satisfy the normalization requirements.

Diff: 2           Page Ref: 316-319

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

72) Explain the pragmatic reason for using surrogate keys.

Answer:  Primary keys are commonly included in indexes, and are used to identify records to be retrieved by users. The ideal primary key is short, numeric and fixed. When the primary key contains a lengthy text field, this creates a large amount of duplicated data that must be frequently manipulated. For these reasons, it is often practical to use a surrogate key that is generated by the system and is relatively small and easy to manipulate.

Diff: 1           Page Ref: 318

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

73) Write the schema to represent the entities below, including tables, the proper placement of the foreign key, and referential integrity constraint.

 

Answer:  STUDENT (StudentID, StuName, StuMajor, StuPhone, AdvisorID)

ADVISOR (AdvisorID, AdvName, AdvOffice, AdvPhone)

 

AdvisorID in STUDENT must exist in AdvisorID in ADVISOR.

Diff: 2           Page Ref: 317-329

AACSB:  Information Technology

Chapter Obj:  Learn how to transform E-R data models into relational designs

Classification:  Concept

 

74) From a pragmatic standpoint, the only important rule of normalization is that the determinant of every functional dependency must be a candidate key.

Answer:  TRUE

Diff: 2           Page Ref: 319-320

AACSB:  Information Technology

Chapter Obj:  Practice applying the normalization process

Classification:  Concept

 

 

75) In terms of normalization, what do the letters BCNF stand for?

1. A) BCNF is not an abbreviation
2. B) Bryce-Cooper Normalization Functionality
3. C) Boyce-Code Normalization Functionality
4. D) Boyce-Codd Normal Form
5. E) Bryce-Cooper Normal Form

Answer:  D

Diff: 3           Page Ref: 319

AACSB:  Information Technology

Chapter Obj:  Practice applying the normalization process

Classification:  Concept

76) Once a table has been defined, it should be examined according to ________ criteria.

Answer:  normalization

Diff: 2           Page Ref: 317

AACSB:  Information Technology

Chapter Obj:  Practice applying the normalization process

Classification:  Concept

 

77) To normalize a relation, the determinant of every functional dependency should be a(n) ________.

Answer:  candidate key

Diff: 2           Page Ref: 320

AACSB:  Information Technology

Chapter Obj:  Practice applying the normalization process

Classification:  Concept

 

78) Relations should always be normalized to the highest degree possible.

Answer:  FALSE

Diff: 1           Page Ref: 321

AACSB:  Information Technology

Chapter Obj:  Understand the need for denormalization

Classification:  Concept

 

79) Which of the following would be a reason to denormalize a relation?

1. A) Relax security
2. B) Lack of design time
3. C) End user preference
4. D) Improve performance
5. E) None of the above

Answer:  D

Diff: 2           Page Ref: 321

AACSB:  Information Technology

Chapter Obj:  Understand the need for denormalization

Classification:  Concept

 

 

80) There are cases where it is possible to normalize a table too far, in which case there may be a need for ________.

Answer:  denormalization

Diff: 2           Page Ref: 321

AACSB:  Information Technology

Chapter Obj:  Understand the need for denormalization

Classification:  Concept

81) What is denormalization and why can it be desirable?

Answer:  Denormalization is the process of consolidating relations that are in a higher normal form into a single relation that is in a lower normal form, thereby making it susceptible to more anomalies. Denormalization can be desirable for two reasons. First, sometimes the act of normalizing a table can cause it to become too cumbersome or contrived, which makes it difficult to work with. Therefore denormalization may be preferable when the dangers of the additional anomalies are considered to be of less importance than the ease of working with the relations. Second, processing multiple tables requires more processing overhead than processing a single table. Therefore, performance can often be improved by using a single, denormalized table than multiple, normalized tables. When the performance gain outweighs the dangers of the additional anomalies, the denormalized table may be preferred.

Diff: 2           Page Ref: 321

AACSB:  Information Technology

Chapter Obj:  Understand the need for denormalization

Classification:  Concept