Database Systems - CH 4 MC, Database Systems - CH 5 MC, Database Systems - CH 6 MC
21. From a structural point of view, 3NF is better than _____. a. 2NF b. 3NF c. 5NF d. 6NF
ANSWER: a
28. A table that has all key attributes defined, has no repeating groups, and all its attributes are dependent on the primary key is said to be in _____. a. 1NF b. 2NF c. 3NF d. 4NF
ANSWER: a
40. From a system functionality point of view, _____ attribute values can be calculated when they are needed to write reports or invoices. a. derived b. atomic c. granular d. historical
ANSWER: a
27. The conceptual model can handle _____ relationships and multivalued attributes. a. 1:1 b. M:N c. 1:M d. 1:N
ANSWER: b
37. A _____ entity has a primary key that is partially or totally derived from the parent entity in the relationship. a. strong b. weak c. business d. child
ANSWER: b
49. According to the "preferably single-attribute" characteristic of a primary key, the primary key: a. must be able to guarantee unique attribute values. b. should have the minimum number of attributes possible. c. should have embedded semantic meaning associated with each attribute. d. must be composed of attributes that are free from security risks or violations.
ANSWER: b
50. Database design is a(n) _____ process based on repetition. a. sequential b. iterative c. linear d. intermittent
ANSWER: b
25. A specialization hierarchy can have _____ level(s) of supertype/subtype relationships. a. zero b. only one c. one or many d. many
ANSWER: d
26. Some very specialized applications may require normalization beyond the _____. a. 1NF b. 2NF c. 3NF d. 4NF
ANSWER: d
27. Of the following normal forms, _____ is mostly of theoretical interest. a. 1NF b. 3NF c. BCNF d. DKNF
ANSWER: d
29. A(n) _____ exists when there are functional dependencies such that Y is functionally dependent on X, Z is functionally dependent on Y, and X is the primary key. a. partial dependency b. repeating group c. atomic attribute d. transitive dependency
ANSWER: d
38. The most likely data type for a surrogate key is _____. a. character b. date c. logical d. numeric
ANSWER: d
41. If an employee within an EMPLOYEE entity has a relationship with itself, that relationship is known as a _____ relationship. a. self b. self-referring c. looping d. recursive
ANSWER: d
43. BCNF can be violated only if the table contains more than one _____ key. a. primary b. candidate c. foreign d. secondary
ANSWER: b
44. When a table contains only one candidate key, _____ are considered to be equivalent. a. the 1NF and the 2NF b. the 3NF and the BCNF c. the 4NF and the 3NF d. the BCNF and the DKNF
ANSWER: b
45. The first step in building an entity-relationship diagram (ERD) is _____. a. developing the initial ERD b. creating a detailed narrative of the organization's description of operations c. identifying the attributes and primary keys that adequately describe the entities d. identifying the business rules based on the description of operations
ANSWER: b
49. Data warehouse routinely uses _____ structures in its complex, multilevel, multisource data environment. a. 1NF b. 2NF c. 3NF d. 4NF
ANSWER: b
50. The "_____" characteristic of a primary key states that the primary key should not have embedded semantic meaning. a. unique values b. nonintelligent c. preferably single-attribute d. security-compliant
ANSWER: b
50. _____ databases reflect the ever-growing demand for greater scope and depth in the data on which decision support systems increasingly rely. a. Normalized b. Data warehouse c. Temporary d. Report
ANSWER: b
24. An attribute that is part of a key is known as a(n) _____ attribute. a. important b. nonprime c. prime d. entity
ANSWER: c
37. In the context of total completeness, in a(n) _____, every supertype occurrence is a member of only one subtype. a. foreign key constraint b. nonunique constraint c. overlapping constraint d. disjoint constraint
ANSWER: d
44. When using the Crow's Foot notation, the associative entity is indicated by _____ relationship lines between the parents and the associative entity. a. dotted b. double c. triple d. solid
ANSWER: d
45. A _____ is a primary key created by a database designer to simplify the identification of entity instances. a. composite key b. compound key c. natural key d. surrogate key
ANSWER: d
46. A table where all attributes are dependent on the primary key but are independent of each other, and no row contains two or more multivalued facts about an entity is said to be in _____. a. 1NF b. 2NF c. 3NF d. 4NF
ANSWER: d
46. Composite primary keys are particularly useful as identifiers of composite entities, where each primary key combination is allowed only once in the _____ relationship. a. 0:1 b. 1:1 c. 1:M d. M:N
ANSWER: d
47. If Tiny College has some departments that are classified as "research only" and do not offer courses, the COURSE entity of the college database would be _____ the DEPARTMENT entity. a. existence-dependent on b. independent of c. mandatory for d. optional to
ANSWER: d
23. A(n) _____ is the set of possible values for a given attribute. a. domain b. range c. identifier d. key
ANSWER: a
23. From a structural point of view, 2NF is better than _____. a. 1NF b. 3NF c. 4NF d. BCNF
ANSWER: a
24. Ideally, an entity identifier is composed of _____ attribute(s). a. one b. two c. three d. six
ANSWER: a
25. A _____ attribute can be further subdivided to yield additional attributes. a. composite b. simple c. single-valued d. multivalued
ANSWER: a
25. Attribute A _____ attribute B if all of the rows in the table that agree in value for attribute A also agree in value for attribute B. a. determines b. derives from c. controls d. owns
ANSWER: a
27. One important inheritance characteristic is that all entity subtypes inherit their _____ key attribute from their supertype. a. primary b. natural c. foreign d. surrogate
ANSWER: a
29. A(n) _____ is the attribute in the supertype entity that determines to which entity subtype each supertype occurrence is related. a. subtype discriminator b. inheritance discriminator c. specialization hierarchy d. entity supertype
ANSWER: a
31. Which of the following is a specialization hierarchy disjoint constraint scenario in case of partial completeness? a. Subtype discriminator can be null. b. Subtype discriminator cannot be null. c. Each supertype occurrence is a member of only one subtype. d. Each supertype occurrence is a member of at least one subtype.
ANSWER: a
33. When the specific cardinalities are not included on the diagram in Crow's Foot notation, cardinality is implied by the use of _____. a. symbols b. attributes c. images d. tables
ANSWER: a
35. An entity is said to be _____-dependent if it can exist in the database only when it is associated with another related entity occurrence. a. existence b. relationship c. business d. data
ANSWER: a
36. Improving _____ leads to more flexible queries. a. atomicity b. normalization c. denormalization d. derived attribute
ANSWER: a
39. A _____ relationship exists when an association is maintained within a single entity. a. unary b. ternary c. strong d. weak
ANSWER: a
41. An entity cluster is formed by combining multiple interrelated entities into _____. a. a single abstract entity object b. multiple abstract entity objects c. a single entity object d. multiple entity objects
ANSWER: a
42. The most important characteristic of an entity is its _____ key, used to uniquely identify each entity instance. a. primary b. natural c. foreign d. surrogate
ANSWER: a
43. The entity relationship model uses the associative entity to represent a(n) _____ relationship between two or more entities. a. M:N b. 1:M c. N:1 d. M:1
ANSWER: a
45. In a _____ situation, one key determines multiple values of two other attributes and those attributes are independent of each other. a. multivalued dependency b. transitive dependency c. partial dependency d. functional dependency
ANSWER: a
48. The "_____" characteristic of a primary key states that the primary key must uniquely identify each entity instance, must be able to guarantee unique values, and must not contain nulls. a. unique values b. nonintelligent c. preferably single-attribute d. security-complaint
ANSWER: a
49. Complex _____ requirements may dictate data transformations, and they may expand the number of entities and attributes within the design. a. information b. entity c. design d. processing
ANSWER: a
21. The extended entity relationship model (EERM) is sometimes referred to as the _____. a. enclosed entity relationship model b. enhanced entity relationship model c. entity clustering relationship model d. extended entity relationship diagram
ANSWER: b
22. Normalization works through a series of stages called normal forms. For most purposes in business database design, _____ stages are as high as you need to go in the normalization process. a. two b. three c. four d. five
ANSWER: b
22. The _____ notation of entity-relationship modelling can be used for both conceptual and implementation modelling. a. Bachman b. UML c. Chen d. Crow's Foot
ANSWER: b
24. Within a specialization hierarchy, every subtype can have _____ supertype(s) to which it is directly related. a. zero b. only one c. one or many d. many
ANSWER: b
26. A _____ attribute is one that cannot be subdivided. a. composite b. simple c. single-valued d. multivalued
ANSWER: b
26. The property of _____ enables an entity subtype to inherit the attributes and relationships of the supertype. a. subtype discriminator b. inheritance c. specialization hierarchy d. entity supertype
ANSWER: b
28. A derived attribute is indicated in the Chen notation by a _____ that connects the attribute and an entity. a. single line b. dashed line c. double dashed line d. double line
ANSWER: b
28. At the implementation level, the supertype and its subtype(s) depicted in a specialization hierarchy maintain a(n) _____ relationship. a. self-referencing b. 1:1 c. 1:M d. M:N
ANSWER: b
29. The decision to store _____ attributes in database tables depends on the processing requirements and the constraints placed on a particular application. a. multivalued b. derived c. single-valued d. composite
ANSWER: b
30. A relationship is an association between _____. a. objects b. entities c. databases d. fields
ANSWER: b
32. In a(n) _____ diagram, the arrows above the attributes indicate all desirable dependencies. a. Chen b. dependency c. functionality d. ER
ANSWER: b
32. In the entity relationship diagram (ERD), cardinality is indicated using the _____ notation, where max is the maximum number of associated entities and min represents the minimum number of associated entities. a. (max, min) b. (min, max) c. [min ... max] d. {min|max}
ANSWER: b
32. Which of the following is a specialization hierarchy overlapping constraint scenario in case of partial completeness? a. Subtype sets are unique. b. Supertype has optional subtypes. c. Subtype discriminators cannot be null. d. Subtype does not have a supertype.
ANSWER: b
33. Dependencies based on only a part of a composite primary key are known as _____ dependencies. a. primary b. partial c. incomplete d. composite
ANSWER: b
37. An atomic attribute _____. a. cannot exist in a relational table b. cannot be further subdivided c. displays multiplicity d. is always chosen to be a foreign key
ANSWER: b
38. The existence of a(n) _____ entity indicates that its minimum cardinality is zero. a. ternary b. optional c. strong d. weak
ANSWER: b
39. Granularity refers to _____. a. the size of a table b. the level of detail represented by the values in a table's row c. the number of attributes represented in a table d. the number of rows in a table
ANSWER: b
39. _____ is the bottom-up process of identifying a higher-level, more generic entity supertype from lower-level entity subtypes. a. Specialization b. Generalization c. Normalization d. Total completeness
ANSWER: b
40. The purpose of an entity _____ is to simplify an entity-relationship diagram (ERD) and thus enhance its readability. a. constraint b. cluster c. interface d. discriminator
ANSWER: b
41. In a real-world environment, we must strike a balance between design integrity and _____. a. robustness b. flexibility c. uniqueness d. ease of use
ANSWER: b
42. To simplify the conceptual design, most higher-order relationships are decomposed into appropriate equivalent _____ relationships whenever possible. a. unary b. binary c. strong d. weak
ANSWER: b
43. A _____ key is a real-world, generally accepted identifier used to uniquely identify real-world objects. a. primary b. natural c. foreign d. surrogate
ANSWER: b
23. The _____ depicts the arrangement of higher-level entity supertypes (parent entities) and lower-level entity subtypes (child entities). a. subtype discriminator b. inheritance c. specialization hierarchy d. entity supertype
ANSWER: c
30. A _____ derives its name from the fact that a collection of multiple entries of the same type can exist for any single key attribute occurrence. a. partial dependency b. transitive dependency c. repeating group d. primary key
ANSWER: c
33. Nonoverlapping subtypes are subtypes that contain a(n) _____ subset of the supertype entity set. a. entity b. subtypes c. unique d. nonunique
ANSWER: c
35. A table that is in 2NF and contains no transitive dependencies is said to be in _____. a. 1NF b. 2NF c. 3NF d. 4NF
ANSWER: c
35. A total completeness constraint is represented by a _____. a. smaller circle inside a bigger circle b. rhombus inside a circle c. double horizontal line under a circle d. single horizontal line above a circle
ANSWER: c
36. A partial completeness constraint is represented by _____. a. a dotted line b. two dashed lines c. a single horizontal line under a circle d. a double horizontal line over a circle
ANSWER: c
38. In the context of total completeness, in a(n) _____, every supertype occurrence is a member of at least one subtype. a. unique constraint b. disjoint constraint c. overlapping constraint d. foreign key constraint
ANSWER: c
40. A _____ relationship exists when three entities are associated. a. unary b. strong c. ternary d. weak
ANSWER: c
42. To generate a surrogate key, Microsoft Access uses a(n) _____ data type. a. character b. sequence c. AutoNumber d. identity
ANSWER: c
46. The Crow's foot symbol with two vertical parallel lines indicates _____ cardinality. a. (0,N) b. (1,N) c. (1,1) d. (0,1)
ANSWER: c
47. A table is in 4NF if it is in 3NF, and _____. a. all attributes must be dependent on the primary key and must be dependent on each other b. all attributes are unrelated c. it has no multivalued dependencies d. no column contains the same values
ANSWER: c
21. The entity relationship diagram (ERD) represents the _____ database as viewed by the end user. a. condensed b. physical c. logical d. conceptual
ANSWER: d
22. A(n)_____ is a generic entity type that is related to one or more entity subtypes. a. subtype discriminator b. inheritance c. specialization hierarchy d. entity supertype
ANSWER: d
30. The default comparison condition for the subtype discriminator attribute is the _____ comparison. a. nonequality b. less than c. greater than d. equality
ANSWER: d
31. A relational table must not contain a(n) _____. a. entity b. attribute c. relationship d. repeating group
ANSWER: d
31. _____ expresses the minimum and maximum number of entity occurrences associated with one occurrence of the related entity. a. Connectivity b. Relationship c. Dependence d. Cardinality
ANSWER: d
34. If a table has multiple candidate keys and one of those candidate keys is a composite key, the table can have _____ based on this composite candidate key even when the primary key chosen is a single attribute. a. Boyce-Codd normal forms b. redundancies c. time-variances d. partial dependencies
ANSWER: d
34. Knowing the minimum and maximum number of _____ occurrences is very helpful at the application software level. a. object b. attribute c. data d. entity
ANSWER: d
34. Overlapping subtypes are subtypes that contain _____ subsets of the supertype entity set. a. null b. exclusive c. solitary d. nonunique
ANSWER: d
36. If an entity can exist apart from all of its related entities, then it is existence-independent, and it is referred to as a(n) _____ entity. a. weak b. alone c. unary d. strong
ANSWER: d
44. If one exists, a data modeler uses a _____ as the primary key of the entity being modeled. a. foreign key b. combination key c. surrogate key d. natural identifier
ANSWER: d
47. The "_____" characteristic of a primary key states that the selected primary key must not be composed of any attribute(s) that might be considered a violation. a. unique values b. nonintelligent c. preferably single-attribute d. security-compliant
ANSWER: d
48. An example of denormalization is using a _____ denormalized table to hold report data. This is required when creating a tabular report in which the columns represent data that are stored in the table as rows. a. transitive b. 3NF c. component d. temporary
ANSWER: d
48. In organizations that generate large number of transactions, _____ are often a top priority in database design. a. relationships among entities b. logical design standards c. naming conventions d. high processing speeds
ANSWER: d
