Lesson 3 Flashcards
automated tools used to design
databases and application programs
Data modeling and design tools
centralized storehouse
of metadata
Repository
software for managing the
database
Database Management System
(DBMS)
storehouse of the data
Database
software using the data
Application Programs
text, graphical displays, menus, etc. for user
User Interface
personnel responsible for maintaining the database
Data/Database Administrators
personnel responsible for designing databases and software
System Developers
people who use the applications and databases
End Users
- First step in the database development process
- Specifies scope and general content
- Overall picture of organizational data
at high level of abstraction:
a. Entity - relationship diagram
(ERD)
b. Descriptions of entity types
c. Relationships between entities
d. Business rules
Enterprise Data Model
Approaches to Database and IS
Development
- SDLC
- Prototyping
● Detailed, well-planned development
process
● Time-consuming, but comprehensive
● Long development cycle
SDLC (System Development Life Cycle)
● 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
Prototyping
- Waterfall approach
- The output from one phase to the
next
System Development Life Cycle
● Purpose: Preliminary understanding
● Deliverable: Request for study
● Database Activity: Enterprise
modeling and early conceptual data
modeling
Planning
● Purpose: Thorough requirements
analysis and structuring
● Deliverable: Functional system
specifications
● Database Activity: Thorough and
integrated conceptual data modelling
Analysis
● Purpose: Information requirements
elicitation
● Deliverable: Detailed design
specifications
● Database Activity: Logical
database design (Transactions,
Forms, display, views, data integrity
and security)
Logical Design
● Purpose: Develop technology and
organizational specifications
● Deliverable: Program/data
structures, technology purchases,
organization redesigns
● Database Activity: Physical
database design (Define database to
DBMS, physical data organization,
database processing programs)
Physical Design
● Purpose: Programming, testing,
training, installation, documentation
● Deliverable: Operational programs,
documentation, training materials
● Database Activity: Database
implementation (Coded programs,
documentation, installation and
conversion)
Implementation
● Purpose: Monitor, repair, enhance
● Deliverable: Periodic audits
● Database Activity: Database
maintenance, performance analysis
and tuning, error corrections
Maintenance
● A classical Rapid Application
Development (RAD) approach.
● One of the most popular RAD
methods is prototyping, which is an
● iterative process of systems
development in which requirements
are converted to a working system
that is continually revised through
close work between analysts and
users.
Prototyping Database Methodology
Conceptual Data Modelling
● Analyze requirements
● Develop preliminary data model
Identify problem
Logical Database Design
● Analyze requirements in detail
● Integrate database views into
conceptual data model
Develop initial prototype
● Define new database contents to
DBMS
● Decide on physical organization for
new data
● Design database processing
programs
Physical Database Design and Definition
● Code database processing
● Install new database contents,
usually from existing data sources
3. Revise and enhance prototype
4. Implement and use prototype
Database Implementation
● Analyze database to ensure it meets
application needs
● Fix errors in database
Database Maintenance
Database Maintenance
● Tune database for improved
performance
● Fix errors in database
Convert to operational system
Different people have different views
of the database
external schema
view of the data architect and data
administrator
conceptual schema
underlying design and
implementation
internal schema
● Can be determined from
business-function/data entity
matrices
● Enterprise model + User Views
● During the Analysis and Logical
Design phases
External Schema
● E-R models
● A single, coherent definition of
enterprise’s data
● The view of data architect or data
admin
● During the Analysis phase
Conceptual Schema
● Logical structures
● Physical structures
Internal Schema
a planned undertaking of
related activities to reach an
objective that has a beginning and
an end.
Project
Managing Projects: People Involved
● Business analysts
● Systems analysts
● Database analysts and data
modelers
● Users
● Programmers
● Database architects
● Data administrators
● Project managers
● Other technical experts
● Personal databases
● Two-tier and N-tier Client/Server
databases
● Enterprise applications
○ Enterprise resource planning
(ERP) systems
○ Data warehousing
implementations
Range of Database Applications
