Computer Science 1032A/B Lecture Notes - Database, Spreadsheet, Cardinality

• School: Western University
• Department: Computer Science
• Course: Computer Science 1032A/B
• Professor: Diane Goldstein

Document Summary

Keeping track of more than one theme. Design reflects the organization that exists within the data. Data model: captures organization of the data, logical representation of the data. What is a model: representation of reality that retains only selected details. Models: powerful tool for validating necessary details and eliminating irrelevant details, associate or map, elements in reality to elements in the model. How do you build a house first, you create a blueprint, a plan, a model. How do you build a database first you make a model, and entity. Relationship model (e-r diagram: visualization (diagram) of the data, describes the logical database, graphical method of mapping the real world. One the e-r model is built, it is used as a blueprint for the real database: model is mapped to an actual relational database. E-r model: most popular for data modeling, introduced in 1976 by peter chen. To describe structured data: a e-r model will consist of: