IS 385 Ch.8 Structuring System Data Requirements

B

A candidate key that has been selected as the unique, identifying characteristic for an entity type is called a(n): A) attribute B) identifier C) secondary key D) gerund

TRUE

A relationship must be turned into an associative entity when the associative entity has other relationships with entities besides the relationship that caused its creation.

B

A relationship that the data modeler chooses to model as an entity type best defines: A) recursive relationship B) associative entity C) domain D) complex relationship

TRUE

A repeating group is a set of two or more multivalued attributes that are logically related.

C

A set of two or more multivalued attributes that are logically related defines: A) relationship B) gerund C) repeating group D) class

C

A simultaneous relationship among instances of three entity types is a: A) unary relationship B) binary relationship C) ternary relationship D) multiple occurrence

TRUE

A true data entity will have many possible instances, each with a distinguishing characteristic, as well as one or more other descriptive pieces of data.

FALSE

A unary relationship is the most common type of relationship encountered in data modeling.

C

An E-R model with attributes is prepared during: A) design B) project identification and selection C) analysis D) project initiation and planning

identifier

An ________ is a candidate key that has been selected as the unique, identifying characteristic for an entity type.

A

An assertion or rule that governs the validity of data manipulation operations such as insert, update, and delete is: A) triggering operation B) entity integrity C) referential integrity constraints D) domains

FALSE

An ellipse represents an entity on an entity-relationship diagram.

FALSE

Analysts should use intelligent keys as identifiers.

FALSE

Business rules are specifications that preserve the integrity of the physical data model.

TRUE

Employee identification number, name, address, and skill are attributes.

B

For each entity, the name of the identifier is: A) identified by using a double-lined ellipse B) underlined on an E-R diagram C) bold on an E-R diagram D) written in all capital letters on an E-R diagram

TRUE

In order to determine the integrity rules, minimum and maximum cardinality, and time dimensions of data, an analyst might ask, "Are values for data characteristics limited in any way?"

TRUE

One way to handle repeating data within an entity is to separate the repeating data into another entity, called a weak entity.

A

Process, logic, and data model descriptions of a system must be consistent and complete because: A) they each describe different but complementary views of the same information system B) they are prepared during the analysis phase C) they are constructed in parallel by separate analyst teams D) programming tasks require the integration of the information contained in the diagrams

FALSE

Processes, rather than data, are the most complex aspects of many modern information systems.

TRUE

Referencing an employee entity, an employee's skills are a multivalued attribute.

FALSE

Social security number, last name, and first name are entity types.

D

Specifications that preserve the integrity of the logical data model are: A) requirements specifications B) integrity restrictions C) business limitations D) business rules

TRUE

The bottom-up approach to data modeling derives a data model by reviewing specific business documents.

TRUE

The characteristics of data captured during data modeling are crucial in the design of databases, programs, computer screens, and printed reports.

A

The condition that causes the operation to be triggered: A) condition B) action C) entity name D) user rule

D

The data manipulation operation (insert, delete, or update) that initiates the operation is called a(n): A) condition B) action C) user rule D) event

TRUE

The minimum cardinality of a relationship is the minimum number of instances of entity B that may be associated with each instance of entity A.

B

The minimum number of instances of entity B that may be associated with each instance of entity A defines the: A) degree of the relationship B) minimum cardinality of the relationship C) maximum cardinality of the relationship D) domain of the relationship

B

The most common format used for data modeling is: A) state-transition diagramming B) entity-relationship diagramming C) process modeling D) decision table diagramming

TRUE

The names of data stores on primitive-level data flow diagrams often correspond to the names of data entities in entity-relationship diagrams.

TRUE

Triggering operations are other business rules that protect the validity of attribute values.

FALSE

Triggers are constraints on valid values for attributes.

TRUE

Universal data models and industry-specific data models are two types of packaged conceptual data models.

B

) If each employee can have more than one skill, then SKILL is referred to as a: A) gerund B) multivalued attribute C) nonexclusive attribute D) repeating attribute

conceptual data model

A ________ is a detailed model that captures the overall structure of organizational data that is independent of any database management system or other implementation considerations.

repeating group

A ________ is a set of two or more multivalued attributes that are logically related.

multivalued attribute

A ________ is an attribute that may take on more than one value for each entity instance.

A

A collection of entities that share common properties or characteristics defines: A) entity type B) entity instance C) entity occurrence D) entity collection

A

A concise statement of the business rule to be enforced by the triggering operation refers to: A) user rule B) condition C) action D) event

FALSE

A ternary relationship is the equivalent of three binary relationships.

TRUE

An entity instance is a single occurrence of an entity type.

TRUE

Book, supplier, and state are entity types.

TRUE

Cardinality is the number of instances of entity B that can (or must) be associated with each instance of entity A.

FALSE

Conceptual data modeling for an Internet-based electronic commerce application differs significantly from the process followed when analyzing the data needs for other types of applications

C

Conceptual data modeling is typically done in parallel with other requirements analysis and structuring steps during: A) logical design B) physical design C) analysis D) implementation

TRUE

Domains are constraints on valid values for attributes.

FALSE

Domains are other business rules that protect the validity of attribute values.

A

During requirements structuring: A) an E-R model represents conceptual data requirements for a particular system B) the conceptual E-R data model is refined before it is translated into a logical format from which database definition and physical database design are done C) an enterprise-wide data model with very broad categories of data and little detail is prepared D) a specific E-R model is built to help explain the scope of a particular systems analysis and design effort

B

If STUDENT and COURSE participate in a relationship, their relationship is a(n): A) unary relationship B) binary relationship C) ternary relationship D) extraordinary relationship

FALSE

On an entity relationship diagram, total specialization is shown by a single line from the supertype to the subtype.

TRUE

Referential integrity constraints are rules concerning the relationships between entity types.

TRUE

Relationships are labeled with verb phrases.

TRUE

The goal of conceptual data modeling is to capture as much of the meaning of data as possible.

TRUE

The primary deliverable from the conceptual data modeling step within the analysis phase is an entity-relationship diagram.

B

The primary deliverable from the conceptual modeling step within the analysis phase is a(n): A) state-transition diagram B) E-R diagram C) context data flow diagram D) decision tree

TRUE

The purpose of the conceptual data model is to show as many rules about the meaning and interrelationships among data as possible.

TRUE

The top-down approach to data modeling derives the business rules for a data model from an intimate understanding of the nature of the business.

FALSE

Use a verb or verb phrase to name an entity.

TRUE

When selecting an identifier, one should choose a candidate key that will not change its value over the life of each instance of the entity type.

A

Which of the following addresses the rules concerning the relationships between entity types? A) referential integrity constraints B) triggering operations C) entity integrity D) domains

B

Which of the following refers to an assertion or rule that governs the validity of data manipulation operations such as insert, update, and delete? A) referential integrity constraints B) triggering operations C) entity integrity D) domains

C

Which of the following specifies that if an entity instance of the supertype is a member of one subtype it cannot simultaneously be a member of any other subtype? A) total specialization rule B) partial specialization rule C) disjoint rule D) overlap rule

D

Some systems developers believe that a data model is the most important part of the statement of information system requirements because: A) the characteristics of data captured during data modeling are crucial in the design of databases, programs, computer screens, and printed reports B) data rather than processes are the most complex aspects of many modern information systems and thus require a central role in structuring system requirements C) the characteristics about data are reasonably permanent D) all of the above

A

The data modeling perspective that derives the business rules for a data model from an intimate understanding of the nature of the business, rather than from any specific information requirements in screens, reports, or business forms, is referred to as the: A) top-down approach B) bottom-up approach C) overview approach D) business approach

A

The number of instances of entity B that can (or must) be associated with each instance of entity A refers to: A) cardinality B) domain C) ternary occurrence D) participation level

C

Which of the following is a true statement? A) Data characteristics are dynamic. B) A data model explains the transient form of an organization. C) An information system design based on a data orientation, rather than a process or logic orientation, should have a longer useful life. D) Data flow paths are permanent.

D

Which of the following refers to the set of all data types and values that an attribute can assume? A) referential integrity constraints B) triggering operations C) entity integrity D) domains

D

Which of the following specifies that an entity instance can simultaneously be a member of two (or more) subtypes? A) total specialization rule B) partial specialization rule C) disjoint rule D) overlap rule

B

Which of the following specifies that an entity instance of the supertype is allowed not to belong to any subtype? A) total specialization rule B) partial specialization rule C) disjoint rule D) overlap rule

A

Which of the following specifies that each entity instance of the supertype must be a member of some subtype in the relationship? A) total specialization rule B) partial specialization rule C) disjoint rule D) overlap rule

C

Which of the following specifies that each instance of an entity type must have a unique identifier that is not null? A) referential integrity constraints B) triggering operations C) entity integrity D) domains

D

A person, place, object, event, or concept in the user environment about which the organization wishes to maintain data refers to a(n): A) attribute B) data element C) relationship D) entity

FALSE

A plural relationship is a relationship that the data modeler chooses to model as entity type.

FALSE

A primary key should be null.

A

A single occurrence of an entity type defines: A) entity instance B) entity appearance C) attribute D) data element

C

A subgrouping of the entities in an entity type that is meaningful to the organization and that shares common attributes or relationships distinct from other subgroupings best defines: A) child node B) disjoined entity C) subtype D) supertype

FALSE

A ternary relationship is a relationship between the instances of one entity type.

C

All of the following are benefits of database patterns and packaged data models EXCEPT: A) purchased models are proven from extensive experience B) systems analysis is facilitated C) purchased models are very specific D) purchased models anticipate future needs

entity-relationship data model

An ________ is a detailed, logical representation of the entities, associations, and data elements for an organization or business area.

attribute

An ________ is a named property or characteristic of an entity that is of interest to the organization.

entity instance

An ________ is a single occurrence of an entity type.

B

An association between the instances of one or more entity types that is of interest to the organization best defines: A) occurrence B) relationship C) coupling D) cardinality

C

An attribute (or combination of attributes) that uniquely identifies each instance of an entity type defines: A) data element occurrence B) trigger C) candidate key D) gerund

B

An attribute that may take on more than one value for each entity instance is referred to as a: A) gerund B) multivalued attribute C) nonexclusive attribute D) supertype

TRUE

An entity is a person, place, object, event, or concept in the user environment about which the organization wishes to maintain data.

TRUE

An identifier is a candidate key that has been selected as the unique, identifying characteristic for an entity type.

TRUE

An order number is a good example of a candidate key.

TRUE

Analysts should substitute single-attribute surrogate keys for large composite keys.

C

If entity B is a mandatory participant, then: A) the minimum cardinality of the relationship is two B) the minimum cardinality of the relationship cannot be defined C) the minimum cardinality of the relationship is one D) the minimum cardinality of the relationship is optional

TRUE

A deliverable from conceptual data modeling is a set of entries about data objects to be stored in the project dictionary or repository.

C

A detailed, logical representation of the entities, associations, and data elements for an organization or business area defines: A) entity-relationship diagram B) conceptual model C) entity-relationship model D) data flow diagram

TRUE

A faculty identification number can serve as an identifier.

FALSE

A join is an association between the instances of one or more entity types that is of interest to the organization.

TRUE

A multivalued attribute is an attribute that may take on more than one value for each entity instance.

A

A named property or characteristic of an entity that is of interest to the organization defines: A) attribute B) relationship C) instance D) gerund

TRUE

Entity integrity means each instance of an entity type must have a unique identifier that is not null.

C

The set of all data types and ranges of values that an attribute can assume defines: A) cardinality B) constraint set C) domain D) reference set

B

The three main constructs of the entity-relationship modeling notation include each of the following except: A) data entities B) data flows C) relationships D) attributes

C

When selecting an identifier, one should: A) use intelligent keys B) use large composite keys instead of single-attribute surrogate keys C) choose a candidate key that will not change its value over the life of each instance of the entity type D) choose a candidate key such that for each instance of the entity, the attribute is guaranteed to have valid values or is null