Chapter 1
The Database Environment and
Development Process
Jason C. H. Chen, Ph.D.
Professor of MIS
School of Business Administration
Gonzaga University
Spokane, WA 99258
chen@jepson.gonzaga.edu
Copyright © Addison Wesley Longman, Inc. & Dr. Chen, Business Database Systems
TM 1-1
Importance of Information
• Information (and energy) are at the
core of everything around us. Our
entire existence (including
businesses) is a process of gathering,
analyzing, understanding, and acting
on the information.
• Modern organizations are said to be
drowning in data but starving for
information.
Copyright © Addison Wesley Longman, Inc. & Dr. Chen, Business Database Systems
TM 1-2
CAREER EARNING POTENTIAL
• Employment for Computer Systems Analysts is
expected to grow much faster than average. Jobs
in this area are expected to increase by 25%
between 2012 and 2020. With a Bachelor's degree
-- the median salary per year for this occupation is
$79,680. It is expected that 127,000 new jobs will
be created in this area by 2020.
•
Source: U.S. Bureau of Labor Statistics.
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TM 1-3
Objectives
•
•
•
•
•
•
•
•
•
•
Define terms
Name limitations of conventional file processing
Explain advantages of databases
Identify costs and risks of databases
List components of database environment
Identify categories of database applications
Describe database system development life cycle
Explain prototyping and agile development approaches
Explain roles of individuals
Explain the three-schema architecture for databases
Copyright © Addison Wesley Longman, Inc. & Dr. Chen, Business Database Systems
TM 1-4
Definitions
• Data: Meaningful facts, text, graphics,
images, sound, video segments.
• Database: An organized collection of
logically related data.
• Information: Data processed to be useful in
decision making.
• Metadata: Data that describes data
(Data about the data).
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TM 1-5
Business and Modeling Environment
Examples:
Model
Meta-Data
Core/Essence
Data
Debt,
Revenue
Business
Reality
Furniture Store
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Invoice
TM 1-6
Business and Modeling Environment
Examples:
Model
Meta-Data
Core/Essence
Data
Debt,
Revenue
Business
Reality
Furniture Store
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Invoice
TM 1-7
Types of Data Processing
• Two types of data processing
– File-based data processing
• e.g., applications developed by Java
– Data-based data processing
• e.g, applications developed by Oracle or
MS/Access)
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TM 1-8
Figure 1-2: Old file processing systems at Pine Valley Furniture
Duplicate
Data
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What is the main
problem in the
company’s processing
systems?
TM 1-9
Disadvantages of File Processing
• Program-Data Dependence
– All programs maintain metadata for each file they use
• Data Redundancy (Duplication of data)
– Different systems/programs have separate copies of the same data
• Limited Data Sharing
– No centralized control of data
• Lengthy Development Times
– Programmers must design their own file formats
• Excessive Program Maintenance
– 80% of of information systems budget
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Problems with Data Dependency
 Each application programmer must maintain
their own data
 Each application program needs to include
code for the metadata of each file
 Each application program must have its own
processing routines for reading, inserting,
updating and deleting data
 Lack of coordination and central control
 Non-standard file formats
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Problems with Data Redundancy
(conti.)
• Waste of space to have duplicate data
• Causes more maintenance headaches
• The biggest Problem:
– When data changes in one file, could cause
inconsistencies
– Compromises data integrity
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SOLUTION:
The DATABASE Approach
• Central repository of shared data
• Data is managed by a controlling agent
• Stored in a standardized, convenient
form
Requires a Database Management System (DBMS)
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Database Management System

A software system that is used to create, maintain, and provide
controlled access to user databases
Application
#1
(Order Filing)
Application
#2
(Invoicing Sys)
Application
#3
(Payroll Sys.)
DBMS
Database
containing
centralized
shared data
DBMS manages data
resources like an operating
system manages hardware
resources
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TM 1-14
Database Management System
• A DBMS is a data storage and retrieval
system which permits data to be stored nonredundantly while making it appear to the
user as if the data is well-integrated.
• In short, a DBMS is a software package that
manages a data base.
Copyright © Addison Wesley Longman, Inc. & Dr. Chen, Business Database Systems
TM 1-15
Advantages of Database Approach
• Program-Data Independence
– Metadata stored in DBMS, so applications don’t need to worry
about data formats (you will know this when you learn Oracle)
– Data queries/updates managed by DBMS so programs don’t
need to process data access routines
– Results in: increased application development and maintenance
productivity
• Minimal Data Redundancy
– Leads to increased data integrity/consistency
Copyright © Addison Wesley Longman, Inc. & Dr. Chen, Business Database Systems
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Advantages of Database Approach
•
•
•
•
Program-data independence
Planned data redundancy
Improved data consistency
Improved Data Sharing
– Different users get different views of the data
• Improved productivity of application development
• Enforcement of Standards
– All data access is done in the same way
• Improved Data Quality
– Constraints, data validation rules
• Improved data accessibility and responsiveness
– Use of standard data query language (SQL)
• Reduced program maintenance
• Improved decision support
• Security, Backup/Recovery, Concurrency (not in Table 1-3)
– Disaster recovery is easier
Copyright © Addison Wesley Longman, Inc. & Dr. Chen, Business Database Systems
TM 1-17
Costs and Risks of the
Database Approach
• New specialized personnel
• Up-front costs:
– Installation Management Cost and Complexity
– Conversion Costs
• Ongoing Costs
– Requires New, Specialized Personnel
– Need for Explicit Backup and Recovery
• Organizational Conflict
– Old habits die hard
• Other hidden costs
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TM 1-18
Why Do We Still Learn
File Processing Systems?
• File processing systems are
still widely used today,
especially for backing up
database systems.
• Understanding the problems
and limitations inherent in file
processing systems can help
us avoid these same problems
when designing database.
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Elements of the Database Approach
• 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
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A Data Model on Customer and Order
Segment of an Enterprise Data Model
CUSTOMER
ORDER
M ORDER?
Q1. One CUSTOMER normally places ___
1 CUSTOMER?
Q2. One ORDER normally is placed by __
How about the relationship between ORDER and PRODUCT?
(see next slide)
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A Data Model on Customer and Order
Segment of an Enterprise Data Model
CUSTOMER
ORDER
M ORDER?
Q1. One CUSTOMER normally places ___
1 CUSTOMER?
Q2. One ORDER normally is placed by __
How about the relationship between ORDER and PRODUCT?
(see next slide)
Copyright © Addison Wesley Longman, Inc. & Dr. Chen, Business Database Systems
TM 1-22
Figure 1-3(a): Comparison of enterprise and project level data
models
ORDER
ORDER_NUMBER
Customer_ID
Order_Date
Q3. One PRODUCT normally is
contained in M
__ ORDER?
Q4. One ORDER normally contains
__ PRODUCT?
M
Copyright © Addison Wesley Longman, Inc. & Dr. Chen, Business Database Systems
TM 1-23
Figure 1-3(a): Comparison of enterprise and project level data models
ORDER
ORDER_NUMBER
Customer_ID
Order_Date
Q3. One PRODUCT normally is
contained in M
__ ORDER?
Q4. One ORDER normally contains
__ PRODUCT?
M
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TM 1-24
Figure 1-3: Comparison of enterprise and project level data models
(a) Segment of an Enterprise Data Model
Q: what are two major differences
between (a) & (b)?
(b) Segment of a Project-Level Data Model
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FIGURE 1-15: Project data model for Home Office product line
marketing support system
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Figure 1-3 Segment from Enterprise Data Model
Figure 3
Enterprise data model is a graphical model that shows the high-level
entities for the organization and the relationship among these entities.
(E/R Diagram)
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Figure 1-3 Segment from enterprise data model
Figure 3
One customer may place many
orders, but each order is placed
by a single customer
 One-to-many relationship
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TM 1-28
Figure 1-3 Segment from enterprise data model
One order has many order lines;
each order line is associated
with a single order
 One-to-many relationship
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TM 1-29
Figure 1-3 Segment from enterprise data model
Figure 3
One product can be in many
order lines, each order line refers
to a single product
 One-to-many relationship
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TM 1-30
Figure 1-3 Segment from enterprise data model
Figure 3
Therefore, one order involves
many products and one product
is involved in many orders
 Many-to-many relationship
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Figure 1-4 Enterprise data model for Figure 1-3 segments
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Figure 1-5 Components of the Database Environment
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Components of the
Database Environment
• CASE Tools–computer-aided software engineering
• Repository–centralized storehouse of metadata
• Database Management System (DBMS) –software for
managing the database
• Database–storehouse of the data
• Application Programs–software using the data
• User Interface–text and graphical displays to users
• Data/Database Administrators–personnel responsible for
maintaining the database
• System Developers–personnel responsible for designing
databases and software
• End Users–people who use the applications and databases
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34
Evolution of Database Technologies
•
•
•
•
•
•
•
Flat files - 1960s - 1980s
Hierarchical – 1970s - 1990s
Network – 1970s - 1990s
Relational – 1980s - present
Object-oriented – 1990s - present
Object-relational – 1990s - present
Data warehousing – 1980s - present
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Figure 1-10a Evolution of Database Technologies
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Figure 1-10b Database architecture
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Figure 1-10b Database architecture
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The Range of Database Applications
• Personal databases
• Two-tier Client/Server databases
• Multitier/N Client/Server (or called web-enabled)
databases
• Enterprise applications
– Enterprise resource planning (ERP) systems
– Data warehousing implementations
(Local Area Network)
(Web-enabled Database )
(WAN)
(Wide Area Network)
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TM 1-39
Figure 1-11 Two-tier database with local
area network
Chapter 1
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TM 1-40
Figure 1-12 Three-tiered client/server database
architecture
Chapter 1
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Muti/N-tier: Web-Enabled Databases
• Web applications requiring databases
–
–
–
–
–
Customer relationship management (CRM)
Business-to-consumer (B2C)
Electronic data interchange (EDI)
Private intranets
XML-defined Web services
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42
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Enterprise Applications
• Enterprise Resource Planning (ERP)
– Integrate all enterprise functions (manufacturing,
finance, sales, marketing, inventory, accounting,
human resources)
• Data Warehousing implementation
– Integrated decision support system derived from
various operational databases
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TM 1-43
Break ! (Ch. 1)
Exercise #1 (p.44)
Homework:
1. Complete chapter1 quiz by Sunday evening.
2. HW#12 (a) only (homework assignment
- high-level (no attributes)
- draw by Visio clearly
- turn in a hardcopy next class
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TM 1-44
Be Prepared for ...
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TM 1-45
Discuss HW
• HW#12 (a)
• Volunteer?
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TM 1-46
Enterprise Data Model
Enterprise data model is a graphical model that
shows the high-level entities for the organization and
the relationship among these entities. (E/R Diagram)
• Enterprise data modeling is the first
step in database development, in
which the scope and general
contents of organizational
databases are specified.
• Descriptions of entity types
Q: Is ER/M a top• Relationships between entities
down or bottom-up
approach?
• Business rules
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Database Design
• Systems Development Life Cycle (SDLC)
• Entity-relationship model (E-R model)
• Normalization
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TM 1-48
Systems Development Life Cycle
Understand the
Business
Problem or
Opportunity
Develop an
Information
System
Solution
Systems Investigation
(Definition) Product:
Feasibility Study
Systems Analysis
Product:
Functional Requirements
Systems Design
Product:
System Specifications
Implement
the Information
System
Solution
Systems Implementation
Product:
Operational System
Systems Maintenance
Product:
Improved System
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TM 1-49
Steps in the Database
Development Process
• Enterprise Modeling
• Conceptual Data Modeling
– Cuts across Project Initiation and Planning &
Analysis phases of SDLC
•
•
•
•
Logical Database Design (E/R)
Physical Database Design and Creation
Database Implementation
Database Maintenance
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TM 1-50
Life Cycle Phases of DA and DBA (Ch.11)
Database Planning
Database Analysis
Database Design
Database Implementation
Operations and Maintenance
Growth and Change
Copyright © Addison Wesley Longman, Inc. & Dr. Chen, Business Database Systems
TM 1-51
Two Approaches to Database and IS
Development
• SDLC
– System Development Life Cycle
– Detailed, well-planned (and structured) development
process
– Time-consuming, but comprehensive
– Long development cycle
• Prototyping
–
–
–
–
Rapid application development (RAD)
Cursory attempt at conceptual data modeling
Define database during development of initial prototype
Repeat implementation and maintenance activities with new
prototype versions
– Tool: Oracle Designer
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Database Design
• Systems Development Life Cycle (SDLC)
• Entity-relationship model (E-R model)
• Normalization
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TM 1-53
Systems Development Life Cycle
Understand the
Business
Problem or
Opportunity
Develop an
Information
System
Solution
Systems Investigation
(Definition) Product:
Feasibility Study
Systems Analysis
Product:
Functional Requirements
Systems Design
Product:
System Specifications
Implement
the Information
System
Solution
Systems Implementation
Product:
Operational System
Systems Maintenance
Product:
Improved System
Copyright © Addison Wesley Longman, Inc. & Dr. Chen, Business Database Systems
TM 1-54
Prototyping
• Prototpying is one of the most
popular rapid application
development (RAD) methods.
• It is an iterative process of
system development in which
requirements are converted to
a working system that is
A prototype is a small,
continually revised through
but working system that
close work between analysts
contains only those
and users.
important (not complete)
features.
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TM 1-55
Systems Development Life Cycle
(see also Figure 1-7)
Project Identification
and Selection
Project Initiation
and Planning
Analysis
Logical Design
Physical Design
Implementation
Maintenance
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TM 1-56
Systems Development Life Cycle
(see also Figure 1.7)
Project Identification
and Selection
Purpose --preliminary understanding
Deliverable –request for project
Project Initiation
and Planning
Analysis
Logical Design
Physical Design
Database activity –
enterprise modeling
Implementation
Maintenance
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TM 1-57
Systems Development Life Cycle
(see also Figure 1.7)
Project Identification
and Selection
Purpose – state business situation and solution
Deliverable – request for analysis
Project Initiation
and Planning
Analysis
Logical Design
Physical Design
Database activity –
conceptual data modeling
Implementation
Maintenance
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TM 1-58
Systems Development Life Cycle
(see also Figure 1.7)
Project Identification
and Selection
Purpose –thorough analysis
Deliverable – functional system specifications
Project Initiation
and Planning
Analysis
Logical Design
Physical Design
Database activity –
conceptual data modeling
Implementation
Maintenance
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TM 1-59
Systems Development Life Cycle
(see also Figure 1.7)
Project Identification
and Selection
Project Initiation
and Planning
Purpose –information requirements structure
Deliverable – detailed design specifications
Analysis
Logical Design
Physical Design
Database activity –
logical database design
Implementation
Maintenance
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TM 1-60
Systems Development Life Cycle
(see also Figure 1.7)
Purpose –develop technology specs
Deliverable – program/data
structures, technology purchases,
organization redesigns
Project Identification
and Selection
Project Initiation
and Planning
Analysis
Logical Design
Physical Design
Database activity –
physical database design
Implementation
Maintenance
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TM 1-61
Systems Development Life Cycle
(see also Figure 1.7)
Purpose –programming, testing, training,
installation, documenting
Deliverable – operational programs,
documentation, training materials
Project Identification
and Selection
Project Initiation
and Planning
Analysis
Logical Design
Physical Design
Database activity –
database implementation
Implementation
Maintenance
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TM 1-62
Systems Development Life Cycle
(see also Figure 1.7)
Project Identification
and Selection
Purpose –monitor, repair, enhance
Deliverable – periodic audits
Project Initiation
and Planning
Analysis
Logical Design
Physical Design
Database activity –
database maintenance
Implementation
Maintenance
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TM 1-63
Figure 1-7: Database development activities during
the systems development life cycle (SDLC)
Planning (Enterprise modeling)
Project Identification
and Selection
Project Initiation
and Planning
Conceptual data modeling
Analysis
Upper
CASE tool
(Front-end)
Logical Design
Integrate database views
and perform normalization
Physical Design
Implementation
Lower CASE tool
(Back-end)
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Growth and Change
Maintenance
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Figure 1-8The prototyping methodology and
database development process
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Figure 1-8 The prototyping methodology and
database development process (cont.)
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Figure 1-8 The prototyping methodology and
database development process (cont.)
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Figure 1-8 The prototyping methodology and
database development process (cont.)
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68
Figure 1-8 The prototyping methodology and
database development process (cont.)
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Managing Projects
• Project–a planned undertaking of related
activities to reach an objective that has a
beginning and an end
• Initiated and planned in planning stage of
SDLC
• Executed during analysis, design, and
implementation
• Closed at the end of implementation
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70
Managing Projects: People Involved
• Project is a planned undertaking of related activities to reach an
objective that has a beginning and an end
• People involved:
– Business analysts – work with management and users to analyze business
– Systems analysts - business situation and IS needs
– Database analysts and modelers - requirements and design for the database
component of the IS
– Users - assessment of their information needs and monitor the developed
system meet their needs
– Programmers – design and write computer programs
– Database architects – establish standards
– Database and data administrators - ensure database consistency, integrity
and provide consulting, training etc..
– Project managers – oversees assigned projects
– Other technical experts - network administrators, testers, technical writers
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The Technology Level of Models
• Conceptual models focus on the underlying
content of an information system with no
assumptions about technology
• Logical models assume a general class of
technology (H/S W independent) – a relational
database
• Internal models assume specific technologies –
for example, an Oracle database engine
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Database Schema
• External Schema (during the analysis and logical design phases)
– User Views
– Subsets of Conceptual Schema
– Can be determined from business-function/data entity
matrices
– DBA determines schema for different users
– This is part of people-management in databases
• Conceptual Schema
– ER models (during the analysis phase)– covered in
chapters 2 and 3
• Internal Schema
– Logical structures–covered in Chapter 4
– Physical structures–covered in Chapter 5
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TM 1-73
Figure 1-9 Three-schema architecture
Different people
have different
views of the
database…these
are the external
schema
The internal
schema is the
underlying
design and
implementation`
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Figure 1-9: Three-schema database architecture
External
Schema
Ch. 4
Ch. 2,3,4
Meta-data/
Repository/
D.D.
E/R, OO …
Relations
Ch. 5
Database
Internal
Schema
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N
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Levels of database schemas
• Different schemas are presented to different
users
External View 1
External View 2
External View 3
External level
logical to external mappings
Logical Schema
Logical level
internal to logical mapping
disk
Internal Schema
Internal level
N
Exercise/Homework
Homework
(1) #17 ; p.45; three views with E/R
- Statement View
- Deposit View
- Conceptual View (an integrated view the
above two views)
Hint: account/customer is one of common entity
(Draw by Visio/Word, turn in hardcopy, due next class)
(2) Online Quiz#1 (due date, midnight Sunday)
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FIGURE 1-15 (a): Preliminary data model for Home Office product line
marketing support system
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