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This chapter introduces the essential context for database development, articulating its goals and phases. It discusses various methodologies, such as traditional life cycle models, spiral methodologies, and rapid application development. The importance of data quality measures including completeness, timeliness, and correctness is emphasized. It outlines the skill sets required for effective database design and covers the features of CASE tools, highlighting the distinctions between front-end and back-end tools. This resource provides foundational knowledge crucial for successful information systems development.
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Chapter 4 Introduction to Database Development
Outline • Context for database development • Goals of database development • Phases of database development • CASE tools
Development Alternatives • Difficulties • Operational system is produced late • Rush to begin implementation • Requirements are difficult to capture • Alternative methodologies • Spiral approaches • Rapid application development • Prototypes may reduce risk
Graphical Models • Explicit or implicit • Data model • Process model • Environment interaction model • Emphasize data model
Broad Goals of Database Development • Develop a common vocabulary • Define data meaning • Ensure data quality • Provide efficient implementation
Data Quality Measures • Completeness • Lack of ambiguity • Timeliness • Correctness • Consistency • Reliability
Database Development Phases Conceptual Data Modeling Data requirements ERD Logical Database Design Tables Distributed Database Design Distribution Schema Physical Database Design Internal Schema, Populated DB
Design Skills • Soft • Qualitative • Degree of subjectivity • People-oriented • Hard • Quantitative • Objective • Intensive data analysis
Features of CASE Tools • Diagramming • Documentation • Analysis • Prototyping
Classification of CASE Tools • Front-end vs. Back-end • Front-end emphasize data modeling and logical analysis • Back-end emphasize code generation and physical design • DBMS dependent vs. DBMS independent
Commercial CASE Tools • PowerDesigner 9 • Oracle 9i Designer • Visual Studio .Net Enterprise Architect • ERWin • ER/Studio • Visible Analyst
ER Assistant • CASE tool distributed with the textbook • Customized for this textbook: supports the ERD notation used in Chapters 5 and 6 • Drawing tool • Diagram checking • Easy to use and powerful tool
Summary • Background for second part of the course • Relationship to information systems development • Broad goals • Development phases • CASE tool features