Chapter 6 - Developing data models for business databases. Chapter 5 explained the Crow's Foot notation for entity relationship diagrams. You learned about diagram symbols, relationship patterns, generalization hierarchies, and rules for consistency and completeness. Understanding the notation is a prerequisite for applying it to represent business databases. This chapter explains the development of data models for business databases using the Crow's Foot notation and rules to convert ERDs to table designs. | Chapter 6 Developing Data Models for Business Databases Welcome to Chapter 6 on developing data models for business databases - Extends your knowledge of the notation of ERDs - Data modeling practice on narrative problems - Convert from ERD to table design - Data modeling is challenging - Ambiguity: part science, part art - Opportunity for some creative problem solving Objectives: - Data modeling practice: - Strategies for analyzing a narrative problem - Transformations for considering alternative designs - Avoidance of common design errors - Master data modeling with lots of practice - Apply conversion rules to transform ERD into a table design Outline Guidelines for analyzing business information needs Transformations for generating alternative designs Finalizing an ERD Schema Conversion Analysis of narrative problems: steps to identify entity types, primary keys, and relationships Transformations: Generation of alternatives Can help depict feasible alternatives Finalizing an ERD Documentation Avoiding common design errors Schema conversion: basic rules and specialized rules Alternative notations: Chen, UML Characteristics of Business Data Modeling Problems Poorly defined Conflicting statements Wide scope Missing details Many stakeholders Requirements in many formats Add structure Eliminate irrelevant details Add missing details Narrow scope Business requirements are rarely well structured. Rather, as an analyst you will often face an ill-defined business situation in which you need to add structure. You will need to interact with a variety of stakeholders who sometimes provide competing statements about the database requirements. In collecting the requirements, you will conduct interviews, review documents and system documentation, and examine existing data. To determine the scope of the database, you will need to eliminate irrelevant details and add missing details. On large projects, you may work on a subset of the requirements and then collaborate with a team | Chapter 6 Developing Data Models for Business Databases Welcome to Chapter 6 on developing data models for business databases - Extends your knowledge of the notation of ERDs - Data modeling practice on narrative problems - Convert from ERD to table design - Data modeling is challenging - Ambiguity: part science, part art - Opportunity for some creative problem solving Objectives: - Data modeling practice: - Strategies for analyzing a narrative problem - Transformations for considering alternative designs - Avoidance of common design errors - Master data modeling with lots of practice - Apply conversion rules to transform ERD into a table design Outline Guidelines for analyzing business information needs Transformations for generating alternative designs Finalizing an ERD Schema Conversion Analysis of narrative problems: steps to identify entity types, primary keys, and relationships Transformations: Generation of alternatives Can help depict feasible alternatives Finalizing an ERD .
