DGMB Chap 4

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81) A co-dependency is a constraint between two attributes or two sets of attributes.

Answer: FALSE

83) A relation is in first normal form if it has no more than one multivalued attribute.

Answer: FALSE

85) A transversal dependency is a functional dependency between two or more nonkey attributes.

Answer: FALSE

86) Anomalies do not generally arise out of transitive dependencies.

Answer: FALSE

38) In the figure below, what type of relationship do the relations depict? A) Strong entity/weak entity B) One-to-many C) Ternary D) Many-to-many

B) One-to-many

15) Which of the following violates the atomic property of relations? A) Sam B) Hinz C) Sam Hinz D) Atomic

C) Sam Hinz

31) Two or more attributes having different names but the same meaning are called: A) homonyms. B) aliases. C) synonyms. D) alternate attributes.

C) synonyms.

10) In the SQL language, the ________ statement is used to make table definitions. A) create session B) create table C) create index D) select

B) create table

11) In the figure below, the primary key for "Order Line" is which type of key? A) Composite B) Foreign C) Standard D) Grouped

A) Composite

20) When all multivalued attributes have been removed from a relation, it is said to be in: A) first normal form. B) second normal form. C) Boyce-Codd normal form. D) third normal form.

A) first normal form.

57) View integration is the process of merging relations together.

Answer: TRUE

23) A relation that contains no multivalued attributes and has nonkey attributes solely dependent on the primary key but contains transitive dependencies is in which normal form? A) First B) Second C) Third D) Fourth

B) Second

2) A form of database specification which maps conceptual requirements is called: A) logical specifications. B) response specifications. C) security specifications. D) physical specifications.

Answer: A

1) ________ database specification indicates all the parameters for data storage that are then input to database implementation. A) Logical B) Physical C) Schematic D) Conceptual

Answer: B

47) A composite key consists of only one attribute.

Answer: FALSE

49) A foreign key is a primary key of a relation that also is a primary key in another relation.

Answer: FALSE

51) An enterprise key is a foreign key whose value is unique across all relations.

Answer: FALSE

53) There can be multivalued attributes in a relation.

Answer: FALSE

55) Unlike columns, the rows of a relation may not be interchanged and must be stored in one sequence.

Answer: FALSE

58) A synonym is an attribute that may have more than one meaning.

Answer: FALSE

60) CASE tools can model more complex data relationships, such as ternary relationships.

Answer: FALSE

62) When transforming a weak entity, one should create one relation with both the attributes of the strong entity and the attributes of the weak entity.

Answer: FALSE

63) The primary key of the many side migrates to the one side when transforming a one-to-many relationship.

Answer: FALSE

64) When transforming a one-to-one relationship, a new relation is always created.

Answer: FALSE

66) An identifier assigned to an associative entity is also called a cross-relation key.

Answer: FALSE

68) When transforming a unary many-to-many relationship to relations, a recursive foreign key is used.

Answer: FALSE

69) The relational data model does, at this time, directly support subtype/supertype relationships.

Answer: FALSE

70) Data integrity consists of powerful operations to manipulate data stored in relations.

Answer: FALSE

72) The entity integrity rule states that a primary key attribute can be null.

Answer: FALSE

73) In the relational data model, associations between tables are defined through the use of primary keys.

Answer: FALSE

76) The truncate table statement in SQL creates a new table.

Answer: FALSE

78) An anomaly is a type of flaw in the database server.

Answer: FALSE

46) Data structures include data organized in the form of tables with rows and columns.

Answer: TRUE

48) A primary key is an attribute that uniquely identifies each row in a relation.

Answer: TRUE

50) Sample data are useful for developing prototype applications and for testing queries.

Answer: TRUE

52) One property of a relation is that each attribute within a relation has a unique name.

Answer: TRUE

54) The columns of a relation can be interchanged without changing the meaning or use of the relation.

Answer: TRUE

56) All values that appear in a column of a relation must be taken from the same domain.

Answer: TRUE

59) When two or more attributes describe the same characteristic of an entity, they are synonyms.

Answer: TRUE

61) When a regular entity type contains a multivalued attribute, two new relations are created.

Answer: TRUE

65) If an identifier is not assigned, the default primary key for an associative relation consists of the two primary key attributes from the other two relations.

Answer: TRUE

67) In the figure below, each employee has exactly one manager.

Answer: TRUE

71) The allowable range of values for a given attribute is part of the domain constraint.

Answer: TRUE

42) The figure below is an example of mapping which type of relationship? A) First B) Second C) Unary D) Ternary

D) Ternary

37) In the figure below, what type of relationship do the relations depict? A) Strong entity/weak entity B) Multivalued C) Composite foreign key D) One-to-many

A) Strong entity/weak entity

32) An attribute that may have more than one meaning is called a(n): A) homonym. B) alias. C) double defined attribute. D) synonym.

A) homonym.

16) The entity integrity rule states that: A) no primary key attribute can be null. B) referential integrity must be maintained across all entities. C) each entity must have a primary key. D) a primary key must have only one attribute.

A) no primary key attribute can be null.

34) Understanding the steps involved in transforming EER diagrams into relations is important because: A) one must be able to check the output of a CASE tool. B) there are rarely legitimate alternatives from which to choose. C) CASE tools can model any situation. D) CASE tools model hypothetical business problems.

A) one must be able to check the output of a CASE tool.

43) A rule that states that each foreign key value must match a primary key value in the other relation is called the: A) referential integrity constraint. B) key match rule. C) entity key group rule. D) foreign/primary match rule.

A) referential integrity constraint.

74) A referential integrity constraint is a rule that maintains consistency among the rows of two relations.

Answer: TRUE

75) A cascading delete removes all records in other tables associated with the record to be deleted.

Answer: TRUE

77) A well-structured relation contains minimal redundancy and allows users to manipulate the relation without errors or inconsistencies.

Answer: TRUE

79) When normalizing, the goal is to decompose relations with anomalies to produce smaller, well-structured relations.

Answer: TRUE

80) A relation in fifth normal form may not contain any anomalies.

Answer: TRUE

82) A candidate key is an attribute, or combination of attributes, that uniquely identifies a row in a relation.

Answer: TRUE

84) A partial functional dependency is a functional dependency in which one or more nonkey attributes are functionally dependent on part (but not all) of the primary key.

Answer: TRUE

41) Referring to the figure below, which of the following is NOT true? A) A component is part of an item. B) A component is always used in only one item. C) A component can be part of an item. D) A component may be used in many items.

B) A component is always used in only one item.

18) In the figure below, Customer_ID in the CUSTOMER Table is which type of key? A) Composite B) Candidate C) Standard D) Grouped

B) Candidate

5) ________ is a component of the relational data model included to specify business rules to maintain the integrity of data when they are manipulated. A) Business rule constraint B) Data integrity C) Business integrity D) Data structure

B) Data integrity

14) Which of the following are properties of relations? A) Each attribute has the same name. B) No two rows in a relation are identical. C) There are multivalued attributes in a relation. D) All columns are numeric.

B) No two rows in a relation are identical.

33) An alternative name for an attribute is called a(n): A) synonym. B) alias. C) alternate attribute. D) related characteristic.

B) alias.

9) A primary key that consists of more than one attribute is called a: A) foreign key. B) composite key. C) multivalued key. D) cardinal key.

B) composite key.

36) When a regular entity type contains a multivalued attribute, one must: A) create a single relation with multiple lines for each instance of the multivalued attribute. B) create two new relations, one containing the multivalued attribute. C) create two new relations, both containing the multivalued attribute. D) delete the relation and start over

B) create two new relations, one containing the multivalued attribute.

26) The attribute on the left-hand side of the arrow in a functional dependency is the: A) candidate key. B) determinant. C) foreign key. D) primary key.

B) determinant.

17) The ________ states that no primary key attribute may be null. A) referential integrity constraint B) entity integrity rule C) partial specialization rule D) range domain rule

B) entity integrity rule

22) The normal form which deals with multivalued dependencies is called: A) fifth normal form. B) fourth normal form. C) Boyce-Codd normal form. D) sixth normal form.

B) fourth normal form.

27) A functional dependency in which one or more nonkey attributes are functionally dependent on part, but not all, of the primary key is called a ________ dependency. A) partial key-based B) partial functional C) cross key D) merged relation

B) partial functional

3) Data is represented in the form of: A) data trees. B) tables. C) data notes. D) chairs.

B) tables.

25) A candidate key must satisfy all of the following conditions EXCEPT: A) the key must uniquely identify the row. B) the key must indicate the row's position in the table. C) the key must be nonredundant. D) each nonkey attribute is functionally dependent upon it.

B) the key must indicate the row's position in the table.

21) The normal form which removes any remaining functional dependencies because there was more than one primary key for the same nonkeys is called: A) fifth normal form. B) fourth normal form. C) Boyce-Codd normal form. D) sixth normal form.

C) Boyce-Codd normal form.

29) ________ problems are encountered when removing data with transitive dependencies. A) Insertion B) Modification C) Deletion D) Merging

C) Deletion

44) ________ are anomalies that can be caused by editing data in tables. A) Insertion B) Deletion C) Modification D) Creation

C) Modification

12) Which of the following is NOT a reason to create an instance of a relational schema with sample data? A) Sample data can be used to improve user communications. B) Sample data can be used for prototype generation. C) Sample data can reverse database implementation errors. D) Sample data provide a convenient way to check the accuracy of your design.

C) Sample data can reverse database implementation errors.

35) A nonkey attribute is also called a(n): A) column. B) unimportant datum. C) descriptor. D) address.

C) descriptor.

8) A primary key whose value is unique across all relations is called a(n): A) global primary key. B) inter-table primary key. C) enterprise key. D) foreign global key.

C) enterprise key.

7) An attribute in a relation of a database that serves as the primary key of another relation in the same database is called a: A) link attribute. B) link key. C) foreign key. D) foreign attribute.

C) foreign key.

24) A constraint between two attributes is called a(n): A) functional relation. B) attribute dependency. C) functional dependency. D) functional relation constraint.

C) functional dependency.

13) A domain definition consists of all of the following components EXCEPT: A) domain name. B) data type. C) integrity constraints. D) size.

C) integrity constraints.

19) All of the following are the main goals of normalization EXCEPT: A) minimize data redundancy. B) simplify the enforcement of referential integrity. C) maximize storage space. D) make it easier to maintain data.

C) maximize storage space.

6) An attribute (or attributes) that uniquely identifies each row in a relation is called a: A) column. B) foreign field. C) primary key. D) duplicate key.

C) primary key.

28) A functional dependency between two or more nonkey attributes is called a: A) partial functional dependency. B) partial nonkey dependency. C) transitive dependency. D) partial transitive dependency.

C) transitive dependency.

39) In the figure below, what is depicted? A) A one-to-one relationship B) A unary relationship C) A one-to-many relationship D) An associative entity

D) An associative entity

40) In the figure below, what type of key is depicted? A) Primary B) Recursive primary C) Composite D) Recursive foreign

D) Recursive foreign

30) The need to ________ relations commonly occurs when different views need to be integrated. A) metadata B) system C) drop D) merge

D) merge

4) A two-dimensional table of data sometimes is called a: A) group. B) set. C) declaration. D) relation.

D) relation.

45) A relation that contains minimal redundancy and allows easy use is considered to be: A) clean. B) simple. C) complex. D) well-structured.

D) well-structured.


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