Transcript DBS Development Lifecycle and DB Analysis

DBS Development Lifecycle
&
DB Analysis
Chapter 10 & 11 in Textbook
Stages of DBS
Development lifecycle
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Database Planning
 Identifying how the stages can be completed in the most
effective & efficient way.
 During planning phase, four major activities are performed:
 Review and approve the database project request.
 Prioritize the database project request.
 Allocate resources such as money, people and tools.
 Arrange a development team to develop the database project.
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Database Planning
 Database planning should also include the development of
standards that govern how data will be collected, how the format
should be specified, what necessary documentation will be
needed.
 Two steps:
1. Mission Statement : Major aims for the Database Project.
2. Mission Objectives : Tasks that DB should support, Driven
through Fact Finding techniques: interviews, questionnaire.
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Database Planning
Mission Statement
 Interviewing the business director:
 What is the purpose of your company?
 Why do you need the DB?
 How can the DB solve your problem?
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Database Planning
Mission Statement
 Interviewing Burger King Director:
 What is the purpose of your company?
To prepare and sell quick service food to fulfill our guest's needs in a
cleaner environment than our competitors.
 Why do you need the DB?
We have many branches over the world , that offers different cosines,
which drive a data management problem, sharing of information between
branches ( for examples : favorite meals, number of employees) which
help in business decision making.
 How can the DB solve your problem?
No more paperwork, automating daily tasks, corporation between
branches.
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Database Planning
Mission Statement
Burger King DB project mission statement
The purpose of BK DB project is to maintain the data that is
used & generated to support the fast food business for our client
and to support sharing information between branches and
in decision making.
Clearer view of the project
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Database Planning
Mission Objectives
 Interviewing different staff:
 Job description.
 Daily tasks.
 Data that they deal with.
 Daily reports.
 Type of things they keep track on.
 Customer services.
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Database Planning
Mission Objectives
1. To manage (add, delete, update) data on branches.
2. To manage (add, delete, update) data on staff.
3. To manage (add, delete, update) on meals.
4. To manage (add, delete, update) on clients.
5. To perform searches on branches.
6. To perform searches on staff.
7. To perform searches on meals.
8. To perform searches on clients
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System Definition
 Identify System boundaries at a very high level, e.g.:
 Current users.
 Current application areas.
Example: DreamHome Database System
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System Definition
 Identify User views; Define what is required of a database
application from the perspective of:
 A particular job role (such as Manager or Supervisor) or
 Enterprise application area (such as marketing or personnel).
Example: User Views
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Requirements Collection & Analysis
 Collecting
and analyzing information about the part of
organization to be supported by the database system, and using
this information to identify users’ requirements of new system.
 Identifying the required functionality for a database system is
crucial, as systems with inadequate functionality will fail.
 Information is gathered for each major user view including:
 a description of data used or generated;
 details of how data is to be used/generated;
 any additional requirements for new database system.
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Requirements Collection & Analysis
 An important activity is to decide how to manage the
requirements for a database system with multiple user views.
 Three main approaches:
 Centralized approach;
 View integration approach; (we use this approach)
 Combination of both approaches.
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Requirements Collection & Analysis
Centralized Approach
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Requirements Collection & Analysis
View Integration Approach
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Requirements Collection & Analysis
 Critical to capture necessary facts to build the required database
application.
 These facts are captured using fact-finding techniques.
 When Are Fact-Finding Techniques Used?
 Fact-finding used throughout database application lifecycle.
 Crucial to early stages including database planning, system
definition, and requirements collection and analysis stages.
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Requirements Collection & Analysis
 Fact-Finding Techniques:
1. Examining documentation,
2. Interviewing (unstructured/structured & open/closed ended questions),
3. Observing organization in operation,
4. Research,
5. Questionnaires (free-format and fixed-format).
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Database Design
 Creating a design for a database that will support the
enterprise’s mission statement and mission objectives for the
required database system.
 Main aims:
 To represent data and relationships required
by users and applications.
 To provide a data model which supports transactions.
 To specify a design that meets performance requirements.
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Database Design
 Three main phases of DB design:
 Conceptual Database Design.
• Create a conceptual data model Independent of any implementation details.
 Logical Database Design. (What)
• At this point you know which type of DBMS you will implementing in - e.g.
relational, object-oriented etc (but not the actual DBMS).
• Test the correctness of the data model through normalization.
 Physical Database Design. (How)
• Derive tables & constraints.
• Identify storage structures and access methods.
• Design security features.
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DBMS Selection
 Selection of an appropriate DBMS to support the database
system.
 Undertaken at any time prior to logical design.
 Main steps for selecting a DBMS:
 Define Terms of Reference of study;
 Shortlist two or three products;
 Evaluate products;
 Recommend selection and produce report.
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Application Design
 Design of user interface and application programs that use and
process the database.
 Database design and application design are parallel activities.
 Includes two important activities:
 transaction design;
 user interface design.
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Prototyping
 Building working model of a database system to evaluate how
the final system will look and function.
 Purpose:
 to identify features of a system that work well, or are inadequate;
 to suggest improvements or even new features;
 to clarify the users’ requirements;
 to evaluate feasibility of a particular system design.
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Implementation
 Physical realization of the database and application designs.
 Create database schemas and empty database files. (DDL)
 Create the application programs. (DML and JAVA or C++ ...)
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Data Conversion and Loading
 Transferring any existing data into new database and converting
any existing applications to run on new database.
 Only required when new database system is replacing an old
system.
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Testing
 Process of running the database system with intent of finding
errors.
 Use carefully planned test strategies and realistic data.
 Demonstrates that database and application programs appear
to be working according to requirements.
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Operational Maintenance
 Process of monitoring and maintaining
database system
following installation.
 Operational Maintenance Activities:
 Monitoring performance of system.
 Maintaining and upgrading database application.
 Incorporating new requirements into DB application.
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