Quiz # 1 Concepts

Question 1

What are the THREE development stage models?

Answer 1

Conceptual model

Logical Model

Physical Model

Question 2

What are the THREE development stage models?

Answer 2

Conceptual model

Logical Model

Physical Model

Question 3

What are the THREE development stage models?

Answer 3

Conceptual model

Logical Model

Physical Model

Question 4

What are some advantages of Databases?

Answer 4

-Prevent redundancy, improve consistency
-Program-Data Independence(they are separate)
-Improved data-sharing
-Enforcement of standards
-Reduced program maintenance
-Improved decision support

Question 5

What is the Range of Database applications?

Answer 5

-Personal Databases

-Multitier Client/Server Databases

-Enterprise Applications(
* Enterprise Resource Planning
* Data Warehousing)

Question 6

What are the elements of the database approach?

Answer 6

Data models
 Graphical system capturing nature
and relationship of data
 Enterprise Data Model–high-level
entities and relationships for the
organization
 Project Data Model–more detailed
view, matching data structure in
database or data warehouse

Entities
 Noun form describing a person,
place, object, event, or concept
 Composed of attributes

Relationships
 Between entities
 Usually one-to-many (1:M) or many-
to-many (M:N)

Relational Databases
 Database technology involving tables
(relations) representing
entities and primary/foreign keys
representing relationships

Question 7

Disadvantages of File Processing?

Answer 7

Duplication of Data

Limited Data Sharing

Lengthy Development Times

Excessive Program Maintenance

Question 8

Problems with Data Redundancy?

Answer 8

The biggest problem:
 Data changes in one file could cause
inconsistencies
 Compromises in data integrity

Question 9

Problems with Data Dependency?

Answer 9

Each application programmer must maintain his/her own data

Lack of Coordination and Central Control

Non-standard file formats

Question 10

Costs and Risks of Database Approach?

Answer 10

New, specialized personnel

Installation and management cost and
complexity

Conversion costs

Need for explicit backup and recovery

Organizational conflict

Question 11

What is the Database Approach?

Answer 11

Central repository of shared data

Data is managed by a controlling agent

Stored in a standardized, convenient
form

Requires a Database Management System (DBMS)