CPSC 203 Study Guide - Final Guide: Data Manipulation Language, Unique Key, Aggregate Function

• School: University of Calgary
• Department: Computer Science
• Course: CPSC 203
• Professor: All

Document Summary

Databases: organized collection of data, minimizes redundancy, wastes space and produce anomalies, makes it easier to access and modify data, examples: university and bank records, typically is a collection of tables. Relations: table and relation means the same thing, ex: in the project we have four difference tuples. Database schema (long answer on conversion of er to database schema on final: defines the columns that you have in your tables. Entities: entity: an object that exists in the real world, physically: book, car, student, conceptually: job, route, entity-type: a class of entities, employee, project, department. Relationship degrees: the degree of a relationship is the number of entity types it relates, controls is a binary relationship type, example: project and department, and the relationship is controls. Participation levels: entity types participate, fully (universal participation) represented by a solid line, partially (existential participation) represented by a dotted line, see page 97.