DATABASE LIFECYCLE

• DATABASE LIFE CYCLE

  • for implementing databases, Starting with requirement analysis ending with monitoring and modification.
  • DBLC never ends because database monitoring, modification, and maintenance are part of the cycle. It will continue after databases has been implemented .
  • Encompasses the Lifetime of the database.
• FIVE STAGES IN DATABASE LIFE CYCLYE

  1. REQUIREMENT ANALYSIS
  2. 2. LOGICAL DESIGN
  3. 3. PHYSICAL DESIGN
  4. 4. IMPLEMENTATION
  5. 5. MONITORING, MODIFICATION
• FIVE STAGES IN DATABASE LIFECYCLE

        I.        REQUIREMENTS ANALYSIS

  -         first and most important stage

  -         most labor-intensive for database designer

  -         involves assessing the informational needs of an organization so that a database can be designed to meet those needs.

  -         identify business objects.
• FIVE STAGES IN DATABASE LIFECYCLE

  Database-design stages:

        II   LOGICAL DESIGN 

  a.    CONCEPTUAL MODEL

  o   First part of logical design

  o   Description of the structure of a database.
• FIVE STAGES IN DATABASE LIFECYCLE

  Database-design stages:

        II   LOGICAL DESIGN

  b. ENTITY-RELATIONSHIP (ER) DIAGRAM

  o   A diagram used during the design phase of database development to illustrate the organization of and relationships between data during database design. 
• FIVE STAGES IN DATABASE LIFECYCLE

  Database-design stages

  II. LOGICAL DESIGN

  c.    NORMALIZATION

  o   Process of applying increasingly stringent rules to a relational database to correct any problems associated with poor design.

  o   create conceptual model
• FIVE STAGES IN DATABASE LIFECYCLE

  II. PHYSICAL DESIGN

  -         to maximize database efficiency.

  -         Finding ways to speed up the performance of RDBMS

  -         from and writing data to a database.

  -         Tweak database for performance
• FIVE STAGES IN DATABASE LIFECYCLE

  IV. IMPLEMENTATION

  -         Create SQL tables
• FIVE STAGES IN DATABASE LIFECYCLE

  V. MONITORING, MODIFICATION

  -         Maintenance and update records
• DATABASE INITIAL STUDY

  -         the designer must examine the current system’s operation within the company and determine how and why the current system fails.
• PURPOSE OF DATABASE INITIAL STUDY

  a.    ANALYZE THE COMPANY SITUATION

  -         General conditions in which a company operates, its organizational structure, and its mission.

  -         the database designer must discover what the company’s operational components are, how they function, and how they interact.
• PURPOSE OF DATABASE INITIAL STUDY

  B. DEFINE PROBLEMS AND CONSTRAINSTS

  -         the designer has both formal and informal sources of information.

  -         the process of defining problems might initially appear to be unstructured.

  -         Company end users are often unable to describe precisely the larger scope of company operations or to identify the real problems encountered during company operations.
• PURPOSE OF DATABASE INITIAL STUDY

  a.    DEFINE OBJECTIVES

  -         Proposed database system must be designed to help solve at least the major problems identified during the problem discovery process.
• PURPOSE OF DATABASE INITIAL STUDY

  a.    DEFINE SCOPE AND BOUNDARIES

  -         the designer must recognize the existence of two sets of limits:

  o   scope

  o   boundaries