Transcript Database Concepts

Database Development Cycle
Track 3: Managing Information Using
Database
Objectives
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Database planning
System Definition
Requirements collection and analysis
Database design
DBMS selection
Application design
Prototyping
Implementation
Data Conversion and loading
Testing
Operational Maintenance
Life Cycle
Database Planning
Systems Definition
Requirements Collection
and analysis
DBMS
Selection
Database Design
Application
Design
Implementation
Data Conversion and loading
Prototyping
Testing
Evaluation & Maintenance
Source: http://www.cs/ucf.edu/courses/cgs2545/CH02/index.htm
Database Planning
Current systems evaluation
Development of Standards
Technological feasability
Operational feasability
Economical feasability
Systems definition
Data dictionary
Metadata
Requirements Collection and Analysis
• identifying management information
requirements,
• determining information requirements by
functional area,
• and establishing hardware and software
requirements
Database Design
Conceptual design
Logical design
Physical design
DBMS Selection
* Costs
* Features and Tools
* Underlying model
* Portability
* DBMS hardware requirements
Application design
• Application program design
• User Interface design
Prototyping
Develop the
working model
Abandon
application
Build the
prototype
Implement
Application
Decision
Use and Test
the prototype
Redevelop
Application
Review the
prototype
Begin new
prototype
Implementation
• The physical realisation of the database and
application designs
• the detailed model is converted to the
appropriate implementation model, the data
dictionary is built, the database is
populated, application programs are
developed and users are trained
Data Conversion and Loading &
Testing
• Transferring any existing data into the new
database and converting any existing
applications to run on the new database
• Finding errors
Database Evaluation
• Interviewing and polling users to determine
whether any data needs are unmet.
Operational maintenance
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preventive maintenance (backup)
corrective maintenance (recovery)1
adaptive maintenance
assignment of access
regular monitoring & periodical check up
Data & Database
administration
• Data administration is the management of
the data resources
• Database administration is the management
of physical realisation of the database
application
Database design methodology
• A structured approach that uses procedures,
techniques, tools, and documentation aids to
support and facilitate the process of design.
* Conceptual database design
* Logical database design
* Physical database design
Entity, Attribute, Relationship
Entity
Attribute
Client
Passport
Name
Address
Postcode
Passport No
Exp.Data
Relationship
Itinerary
Date
City
Contact
Conceptual Design Phase
TOP-DOWN
Identify Entities
Identify Relationships
Identify Attributes
BOTTOM-UP
Identify Relationships
Identify Dependencies
DATA
Collect Data
Basic relationships
•One-to-One
•One-to-many
is married to
HUSBAND
WIFE
is married to
has
TRACK
•Many to many Trainer
belongs to
PARTICIPANTS
holds
is helds in
Track
Logical design phase
Conceptual
E.A.R Model
1. REFINE THE CONCEPTUAL MODEL
Refined Conceptual Model
2.APPLY THE RULES OF NORMALIZATION
Logical
Data
Model
Refining the Conceptual model
• Refine the attributes
– example:
• Synonyms
• Hononyms
Physical Database Design
Logical Data Model
Logical Process Model
Track
01
Country
TR
Physical
Implementation
Process
Database creation
CREATE DATABASE
CREATE TABLE
LOAD
Critical Success Factors in
Database Design
• Work interactively with the users as much as possible.
• Follow a structured methodology throughout the data
modelling process.
• Incorporate structural and integrity considerations into
the data models.
• Combine conceptualisation, normalisation, and
transaction validation techniques into the data
modelling methodology.
Exercise (Conceptual design)
Create a conceptual E.A.R model of the database for the following lists. (List up the necessary
DATA ITEMS, set up ENTITIES and their ATTRIBUTES, and identify the relationship among
the entities )
List 1
Track No: 1
Participant
code
Track name: Managing information using Database
Participant
name
Age
Position
Country
Address
List 1 is the list of participants’ information by track
List 2
Country code
Country name
Participant code
Participant name
List 2 is the list of participants’ information by countries
Track name
Answer
Entity
Attribute
Participant
Participant name One
Participant code or
many
Age
Address
Position
Just
one
Track
Track number
Track name
Zero one or many
Just one
Country
Country code
Country name
Relationship
Exercise: Primary and Foreign Key
Please identify primary and foreign key.
Participant
code
Participant
name
Country code
Country name
Age
Position
Track code
Address
Track name
Country code
Participant
code
Primary key
Foreign key
Answer
Participant
code
Participant
name
Country code
Country name
Age
Position
Track code
Address
Track name
Country code
Participant
code