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Lecture Introduction to systems analysis and design: Chapter 7 - Whitten, Bentley

Chapter 7 - Data modeling and analysis. In this chapter you will learn how to use a popular data-modeling tool, entity relationship diagrams, to document the data that must be captured and stored by a system, independently of showing how that data is or will be used—that is, independently of specific inputs, outputs, and processing. You will also learn about a data analysis technique called normalization that is used to ensure that a data model is a “good” data model. | Chapter 7 Data Modeling and Analysis This repository of slides is intended to support the named chapter. The slide repository should be used as follows: Copy the file to a unique name for your course and unit. Edit the file by deleting those slides you don’t want to cover, editing other slides as appropriate to your course, and adding slides as desired. Print the slides to produce transparency masters or print directly to film or present the slides using a computer image projector. Objectives Define data modeling and explain its benefits. Recognize and understand the basic concepts and constructs of a data model. Read and interpret an entity relationship data model. Explain when data models are constructed during a project and where the models are stored. Discover entities and relationships. Construct an entity-relationship context diagram. Discover or invent keys for entities and construct a key-based diagram. Construct a fully attributed entity relationship diagram and describe data | Chapter 7 Data Modeling and Analysis This repository of slides is intended to support the named chapter. The slide repository should be used as follows: Copy the file to a unique name for your course and unit. Edit the file by deleting those slides you don’t want to cover, editing other slides as appropriate to your course, and adding slides as desired. Print the slides to produce transparency masters or print directly to film or present the slides using a computer image projector. Objectives Define data modeling and explain its benefits. Recognize and understand the basic concepts and constructs of a data model. Read and interpret an entity relationship data model. Explain when data models are constructed during a project and where the models are stored. Discover entities and relationships. Construct an entity-relationship context diagram. Discover or invent keys for entities and construct a key-based diagram. Construct a fully attributed entity relationship diagram and describe data structures and attributes to the repository. Normalize a logical data model to remove impurities that can make a database unstable, inflexible, and nonscalable. Describe a useful tool for mapping data requirements to business operating locations. No additional notes Data Modeling Data modeling – a technique for organizing and documenting a system’s data. Sometimes called database modeling. Entity relationship diagram (ERD) – a data model utilizing several notations to depict data in terms of the entities and relationships described by that data. No additional notes Sample Entity Relationship Diagram (ERD) Teaching Notes Be sure to explain that this is merely an example – there are numerous data modeling notations. While they may differ in appearance (symbology) the knowledge that data models are intended to convey the same. Persons: agency, contractor, customer, department, division, employee, instructor, student, supplier. Places: sales region, building, room, branch office, .