Unlock document.
This document is partially blurred.
Unlock all pages and 1 million more documents.
Get Access
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 ________.
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 ________.
37) Explain the representation of a one-to-many strong entity relationship in a relational database
design.
38) Explain the representation of a many-to-many strong entity relationship in a relational
database design.
39) What is an association relationship, and how does it differ from an N:M relationship?
40) How are 1:1, 1:N and N:M relationships handled in Microsoft Access?
41) All recursive relationships are 1:1.
42) Recursive relationships can be represented in the relational model using the same techniques
that are used for binary relationships.
43) What relationship pattern is illustrated in the following schema?
EMPLOYEE (EmployeeID, OfficePhone, Manager)
Manager in EMPLOYEE must exist in EmployeeID in EMPLOYEE
A) Association relationship
B) Intersection relationship
C) Recursive relationship
D) Strong entity relationship
E) Supertype/subtype relationship
44) Which of the following is not true of recursive relationships?
A) When the recursive relationship is M:N, an intersection table is created.
B) The rows of a single table can play two different roles.
C) The techniques for representing the tables are the same as for non-recursive relationships
except the rows are in the same table.
D) Recursive relationships can be 1:1, 1:N, or M:N relationships.
E) Even when the relationship is 1:N, a new table must be defined to represent the relationship.
45) A(n) ________ is a relationship among entities of the same class.
46) How are one-to-one recursive relationships addressed using the relational model?
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.
48) If a weak entity is ID-dependent but not existence-dependent, it can be represented using the
same techniques as a strong entity.
49) The key of the parent entity becomes part of the key of an ID-dependent entity.
50) Which of the following is true about representing a weak entity with the relational model?
A) If the weak entity is existence-dependent, the key of the parent must be part of the key of the
weak entity.
B) If the strong entity has a minimum cardinality of 1, the key of the weak entity must be part of
the strong entity.
C) If the weak entity is ID-dependent, the key of the weak entity must be part of the key of the
parent entity.
D) If the weak entity is ID-dependent, the key of the parent entity must be part of the key of the
weak entity.
E) If the parent entity is existence-dependent, then the minimum cardinality of the weak entity is
zero.
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 ________.
A) when the child entity is ID-dependent
B) when the child entity is non-ID-dependent
C) when the child entity has a 1:1 relationship with the parent entity
D) when the child entity has a 1:N relationship with the parent entity
E) when the child entity has a recursive relationship with the parent entity
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.
53) Explain the representation of ID-dependent weak entities using the relational model.
54) The first step in representing entities using the relational model is to determine which
identifier will be used as the key.
55) An entity needs to be examined according to normalization criteria before creating a table
from it in the relational database design.
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.
57) By default, the identifier of the entity becomes the foreign key of the corresponding table.
58) The ideal primary key is short, numeric, and nonchanging.
59) A surrogate key is appropriate when the primary key of a table contains a lengthy text field.
60) One of the important properties of an attribute is whether or not it is required.
61) The first step in transforming an extended E-R model into a relational database design is to
________.
A) create a table for each relationship
B) evaluate the entities against the normalization criteria
C) create a table for each entity
D) remove any recursive relationships
E) document referential integrity constraints
62) Each attribute of an entity becomes a(n) ________ of a table.
A) column
B) primary key
C) foreign key
D) alternate key
E) either B or D
63) The identifier of the entity becomes the ________ of the corresponding table.
A) primary key
B) foreign key
C) supertype
D) subtype
E) either A or B
64) A surrogate key should be considered when ________.
A) a relationship is M:N
B) a composite key is required
C) the key contains a lengthy text field
D) the key contains a number
E) an index needs to be created
65) Which of the following is not true about surrogate keys?
A) They are identifiers that are supplied by the system, not the users.
B) They have no meaning to the users.
C) They are nonunique within a table.
D) They can be problematic when combining databases.
E) The DBMS will not allow their values to be changed.
66) One of the important properties of a column is whether or not it is ________.
A) found in more than one entity
B) required
C) character or numeric
D) subject to normalization
E) subject to denormalization
67) In a relational database design, all relationships are expressed by ________.
A) creating a primary key
B) creating a foreign key
C) creating a supertype
D) creating a subtype
E) creating a line between entities
68) After a 1:1 relationship has been created between two tables in Microsoft Access, the
Relationship Type of One-To-One appears ________.
A) in the Relationship Type property of the primary key column in table Design View
B) in the Relationship Type property of the foreign key column in table Design View
C) in the table object in the Relationships window
D) in the Show Table dialog box
E) in the Edit Relationships dialog box
69) The first step of database design is to define a table for each ________.
70) To represent a many-to-many relationship in the relational model, a(n) ________ table is
used.
71) Explain the process of representing an entity using the relational model.
72) Explain the pragmatic reason for using surrogate keys.
73) Write the schema to represent the entities below, including tables, the proper placement of
the foreign key, and referential integrity constraint.
74) From a pragmatic standpoint, the only important rule of normalization is that the determinant
of every functional dependency must be a candidate key.
75) In terms of normalization, what do the letters BCNF stand for?
A) BCNF is not an abbreviation
B) Bryce-Cooper Normalization Functionality
C) Boyce-Code Normalization Functionality
D) Boyce-Codd Normal Form
E) Bryce-Cooper Normal Form
76) Once a table has been defined, it should be examined according to ________ criteria.
77) To normalize a relation, the determinant of every functional dependency should be a(n)
________.
78) Relations should always be normalized to the highest degree possible.
79) Which of the following would be a reason to denormalize a relation?
A) Relax security
B) Lack of design time
C) End user preference
D) Improve performance
E) None of the above
80) There are cases where it is possible to normalize a table too far, in which case there may be a
need for ________.
81) What is denormalization and why can it be desirable?
