hw2 c7-c9 hbnh

Candidate *

A ________ key is an attribute (or combination of attributes) that uniquely identifies each instance of an entity type.

Binary

A ________ relationship is a relationship between instances of two entity types and is the most common type of relationship encountered in data modeling.

Sinks

A common mistake many people make when they are just learning to draw E-R diagrams, especially if they already know how to do data flow diagramming, is to confuse data entities with ________ and relationships with data flows.

One

A unary relationship is a relationship between the instances of ________ entity type(s).

Conceptual

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

Attribute

A(n) ________ is a named property or characteristic of an entity that is of interest to the organization.

Relationship

A(n) ________ is an association between the instances of one or more entity types that is of interest to the organization.

Multivalued attribute

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

Type

An entity ________ is a collection of entities that share common properties or characteristics.

Instance

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

Type; instances

An entity ________ is described just once in a data model, whereas many ________ of that may be represented by data stored in the database.

True

An entity has its own identity that distinguishes it from each other entity.

False *

During logical database design, you must account for every data element on a system input or output-form or report-and on the flow chart.

Data

During requirements structuring, a ________ model represents conceptual data requirements for a particular system.

Row

Each ________ of a relation corresponds to a record that contains data values for an entity.

Name

Each entity type in an E-R model is given a ________ because it represents a class or set, it is singular.

Second *

In ________ normal form, each nonprimary key attribute is identified by the whole key (what we call full functional dependency).

Third

In ________ normal form, nonprimary key attributes do not depend on each other (what we call no transitive dependencies).

Conceptual

In logical database modeling and design, we translate the ________ E-R data model for the application or enterprise, developed without explicit consideration of specific user interfaces, into normalized data requirements.

True *

Logical database design is driven not only from the previously developed E-R data model for the application or enterprise but also from form and report layouts.

True

Mastery of the requirements structuring methods and techniques is critical to one's success on a systems development project team.

Attributes and secondary keys *

On what basis are objects referenced, selected, qualified, sorted, and categorized?

Redundancy

One purpose of database design is to structure the data in stable structures, called normalized tables, that are not likely to change over time and that have minimal ________.

Cardinality

The ________ defines the number of instances of entity B that can (or must) be associated with each instance of entity A.

Degree

The ________ of a relationship is the number of entity types that participate in that relationship.

Entity-relationship

The most common format used for data modeling is ________ diagramming.

Nonprimary

The result of normalization is that every ________ key attribute depends upon the whole primary key.

Four

There are ________ key steps in logical database modeling and design

Primary key

What unique characteristic(s) distinguish(es) each object from other objects of the same type?

Physical *

________ database design is driven not only from the previously developed E-R data model for the application or enterprise but also from form and report layouts.

Normalization

________ is a process for converting complex data structures into simple, stable data structures.

False

A foreign key is an attribute (or combination of attributes) whose value is unique across all occurrences of a relation.

Attributes

A functional dependency is a particular relationship between two ________.

False

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

Unary

A recursive relationship is also known as a ________ relationship.