Unlock document.
This document is partially blurred.
Unlock all pages and 1 million more documents.
Get Access
Database Concepts, 8e (Kroenke)
Chapter 2 The Relational Model
1) A key must be unique.
2) Ensuring that every value of a foreign key matches a value of the corresponding primary key
is an example of a referential integrity constraint.
3) A double arrow notation, A →→ B, is used to indicate a multivalued dependency.
4) Microsoft Access forms can only contain data from one table.
5) Which of the following terms is synonymous with "tuple"?
A) Attribute
B) Table
C) Field
D) Row
E) Relation
6) Which of the following is not true about null values?
A) A null value can mean that the value is unknown.
B) A null value is ambiguous.
C) A null value can mean that the value is known to be blank.
D) A null value can mean that no value for the field is appropriate.
E) Null values cannot be avoided.
7) Explain the terms relation, tuple, and attribute.
8) Explain the possible interpretations of a null value.
9) While the relational model for databases appears to hold much promise, few commercial
databases have implemented it.
10) Every cell in a relation can hold only a single value.
11) In the relational model, each row of a table contains data that represents an attribute of the
entity.
12) Which of the following terms is synonymous with "relation"?
A) Attribute
B) Table
C) Record
D) Row
E) Tuple
13) ________ was the developer of the relational model for databases.
14) Although Microsoft Access is a personal database, the database tables in Access are still
subject to ________ if they are not well-formed.
15) To be considered a composite key, a key must contain at least two attributes.
16) Candidate keys may or may not be unique.
17) The primary key is used both to identify unique rows in a relation and to represent rows in
relationships.
18) Null values can cause problems because they are ambiguous.
19) Which of the following is true about a key?
A) It may be unique.
B) It may be non-unique.
C) It can only identify one row.
D) Both A and B
E) None of the above
20) A key that contains more than one attribute is called a(n) ________.
A) composite key
B) complex key
C) multi-key
D) n-key
E) candidate key
21) A primary key is ________.
A) not required to be unique
B) used to represent columns in relationships
C) a candidate key
D) always automatically generated by the DBMS
E) comprised of exactly one attribute
22) A candidate key is ________.
A) never a primary key
B) a combination of two or more attributes
C) is always automatically generated by the DBMS
D) a candidate to be the primary key
E) None of the above
23) A(n) ________ is one or more columns of a relation that is used to identify a row.
24) A key that contains two or more attributes is called a(n) ________ key.
25) The unique keys that are not chosen to be the primary key are called ________ keys.
26) Distinguish between the primary key and a candidate key.
27) Briefly describe the various tasks of the primary key.
28) If the condition exists such that knowing the value of attribute X determines the value of
attribute Y, then attribute Y is functionally dependent on attribute X.
29) Given the functional dependency for the attributes of ENTITY1, X → (A, B, C), X is a
candidate key for the relation ENTITY1 (A, B, C, X).
30) Given the below functional dependency,
MedicineCode → (MedicineName, ShelfLife, Manufacturer, Dosage)
which of the following statements is not known to be true?
A) MedicineCode is a determinant.
B) MedicineName is a determinant.
C) Manufacturer is functionally dependent on MedicineCode.
D) ShelfLife is functionally dependent on MedicineCode.
E) MedicineCode is a candidate key of the relation MEDICINE (MedicineName, ShelfLife,
Manufacturer, Dosage).
31) Which of the following functional dependency diagrams accurately represents the following
situation:
• A campus has many buildings.
• Each building has a unique name.
• Each building has many rooms.
• All rooms in any given building are numbered sequentially starting at "101."
• Each room has a certain capacity, although many rooms in the same building or different
buildings may have the same capacity.
• Each room is assigned to a single department.
• A department may have many rooms in one or more buildings, each with the same or
different capacities.
A) BuildingName → (RoomNumber, Capacity, Department)
B) RoomNumber → (BuildingName, Department, Capacity)
C) (Department, Capacity) → (BuildingName, RoomNumber)
D) (BuildingName, Capacity) → (Department, RoomNumber)
E) (BuildingName, RoomNumber) → (Capacity, Department)
32) The relationship between two attributes that denotes that if the value of the first attribute is
known, then the value of the second attribute can be determined, is called a(n) ________.
33) The key that has been designated the ________ key of a relation functionally determines all
the other attributes in the relation.
34) Explain the concept of a functional dependency.
35) Surrogate key values have no meaning to the users.
36) Since surrogate keys are used to uniquely identify rows, their values are normally displayed
prominently on all forms and reports for the users to see.
37) The use of surrogate keys usually complicates application programming since most DBMS
products require the application program to generate surrogate key values.
38) A surrogate key may be appropriate under which of the following circumstances?
A) The primary key is not unique.
B) The primary key is numeric.
C) The available candidate keys would be prone to typographical errors.
D) The available candidate keys have little meaning to the users.
E) The relation only has one attribute.
39) Which of the following is not true of surrogate keys?
A) They are meaningful to the users.
B) They are numeric.
C) They are usually generated by the DBMS.
D) They are unique.
E) They are usually hidden on forms and reports.
40) In SQL Server, the starting value of a surrogate key is called the ________.
A) identity
B) identity increment
C) identity Start
D) identity Seed
E) identity property
41) A(n) ________ is a unique, numeric value that is appended to the relation to serve as the
primary key.
42) Explain the concept of a surrogate key.
43) Normalization is the process of removing all functional dependencies from a relation.
44) To create a well-formed relation through normalization, every determinant must be a
candidate key.
45) Any table that meets the definition of a relation is said to be in second normal form.
46) The first step of the normalization process is to identify all the candidate keys of a relation.
47) In the normalization process, it is not necessary to identify all the functional dependencies in
a relation.
48) In the normalization process, it is necessary to identify all the determinants in a relation.
49) In the normalization process, if you find a candidate key that is not a primary key, then you
have determined that the relation needs to be broken into two or more other relations.
50) In the normalization process, if you find that every determinant in a relation is a candidate
key, then you have determined that the relation is well formed.
51) Since Microsoft Access is a personal database, it is not subject to the modification problems
that occur in other relational databases.
52) In Microsoft Access, relationships between tables are created in the Relationships window.
53) In Microsoft Access, foreign keys are designated by using the Foreign Key button in the
toolbar.
54) In Microsoft Access, a relationship is created by dragging a foreign key column and
dropping it on top of the corresponding primary key.
55) One important relational design principle is that ________.
A) every determinant must be a candidate key
B) every candidate key must not be a determinant
C) every primary key must be a surrogate key
D) every determinant must be functionally dependent on the primary key
E) every primary key must be functionally dependent on every determinant
56) During the normalization process, the remedy for a relation that is not well formed is to
________.
A) create a surrogate key
B) create a functional dependency
C) break it into two or more relations that are well formed
D) combine it with another relation that is well formed
E) convert it into a list
57) A table that meets the requirements of a relation is said to be in which normal form?
A) Relational normal form (RNF)
B) First normal form
C) Second normal form
D) Boyce-Codd normal form
E) Domain/key normal form
58) The first step of the normalization process is to ________.
A) identify all the candidate keys of a relation
B) identify all the foreign keys of a relation
C) identify all the functional dependencies of a relation
D) identify all the determinants of a relation
E) split the relation into two or more new relations
59) In the normalization process, it is not necessary to ________.
A) identify all the candidate keys of a relation
B) identify all the foreign keys of a relation
C) identify all the functional dependencies of a relation
D) identify all the determinants of a relation
E) determine if every determinant is a candidate key
60) In the normalization process, if you find a candidate key that is not a primary key then you
should ________.
A) place the columns of the functional dependency in a new relation
B) make the determinant of the functional dependency the primary key of the new relation
C) leave a copy of the determinant as a foreign key in the original relation
D) remove the determinant from the original relation
E) None of the above
61) In the normalization process, if you find a candidate key that is not a determinant then you
should not ________.
A) place the columns of the functional dependency in a new relation
B) make the determinant of the functional dependency the primary key of the new relation
C) leave a copy of the determinant as a foreign key in the original relation
D) rename the determinant to another attribute description
E) create a referential integrity constraint between the original relation and the new relation
62) In the normalization process, if you find that every determinant in a relation is a candidate
key then you have determined that ________.
A) the relation is well formed
B) the relation needs to be broken into two or more new relations
C) surrogate keys in the relation may not be correctly linked to other relations
D) the relation needs to have foreign keys added in order to be correctly linked to other relations
E) referential integrity constraints concerning the relation need to be established
63) To be a well-formed relation, every ________ in the relation must be a candidate key.
64) Any table that meets the requirements of a(n) ________ is in first normal form.
65) What is normalization?
66) What are the basic steps of the normalization process?
67) What is a multivalued dependency, and how do they affect the normalization process?
68) To represent a relationship in the relational model, the primary key of one relation is placed
into a second relation.
69) When used to represent a relationship, the primary key must have the same name as the
corresponding foreign key.
70) When the primary key of one relation is placed into a second relation, it is called a
________.
A) field key
B) referential integrity
C) foreign key
D) candidate key
E) relocated key
71) Given the relations:
STUDENT (SID, StudentName, Major, AdvisorID)
ADVISOR (AdvisorID, AdvisorName, Office, Phone)
such that each student is assigned to one advisor, which of the following is true?
A) SID is both a primary key and a foreign key.
B) AdvisorName is a determinant.
C) AdvisorID is a foreign key.
D) Phone is a candidate key.
E) Major is a candidate key.
72) A rule that requires that the values in a foreign key must have a matching value in the
primary key to which the foreign key corresponds is called ________.
A) normalization
B) a referential integrity constraint
C) a key matching constraint
D) a functional dependency
E) synchronization
73) In Microsoft Access, relationships between tables are created ________.
A) by the Relationships button on the Create command tab
B) by the Relationships button on the Home command tab
C) in the Relationships window
D) in the Table window of the table containing the primary key
E) in the Table window of the table containing the foreign key
74) In Microsoft Access, a relationship between two tables is created ________.
A) by entering the name of the foreign key in the appropriate table in Design View
B) by entering the name of the primary key in the appropriate table in Design View
C) by dragging the primary key column of one table onto the foreign key column of the other
table in the Relationships window
D) by dragging the foreign key column of one table onto the primary key column of the other
table in the Relationships window
E) by dragging the primary key column of one table onto the primary key column of the other
table in the Relationships window
75) In Microsoft Access, referential integrity constraints are created ________.
A) by setting a property value on the primary key in the table which contains it
B) by setting a property value on the foreign key in the table which contains it
C) by setting a property value on the primary key in the Relationships window
D) by setting a property value on the foreign key in the Relationships window
E) by checking the Enforce Referential Integrity check box in the Edit Relationships dialog box
76) In Microsoft Access, the relationship between two tables is not actually created until
________.
A) the OK button in the Create Relationships dialog box is clicked
B) the Create button in the Create Relationships dialog box is clicked
C) the OK button in the Edit Relationships dialog box is clicked
D) the Create button in the Edit Relationships dialog box is clicked
E) the Join button in the Edit Relationships dialog box is clicked
77) When the primary key of one relation is placed in a second relation to represent a
relationship, the attribute in the second relation is called a(n) ________ key.
78) A rule that requires every value in a foreign key to match values in the corresponding
primary key is called a(n) ________ constraint.
79) In Microsoft Access, relationships between tables are built in the ________.
80) In Microsoft Access, the Relationships window is accessed by using the ________ button on
the Database tools command tab.
81) To create a relationship in Microsoft Access, we drag and drop the ________ of a table.
82) In Microsoft Access, referential integrity constraints are created in the ________.
83) Explain the concept of a foreign key.
84) Explain how to create a relationship in Microsoft Access.
85) Every table is a relation, but not every relation is a table.
86) Every relation is a table, but not every table is a relation.
87) Which of the following is not true about a relation?
A) A relation is a two-dimensional table.
B) The cells of a relation must hold a single value.
C) A relation may have duplicate column names.
D) A relation may not have duplicate rows.
E) The order of the rows of a relation is insignificant.
88) Which of the following is true about a relation?
A) The order of the columns in a relation must go from largest to smallest.
B) All entries in any column must be of the same kind.
C) A relation may have duplicate column names.
D) A relation may have duplicate rows.
E) A relation may have multiple names.
89) What requirements must a two-dimensional table satisfy in order to be a relation?
90) In practice, why would tables that have duplicate rows be allowed?
