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Assignment 4: Database Modeling and Normalization1Assignment 4: Database Modeling and NormalizationKevin A. NockCIS/5151/29/2017Dr. Osama Morad
Assignment 4: Database Modeling and Normalization2Database Modeling and NormalizationThe Entity Relationship Model (ERD) is the model to represent the relationships amongthe entities. It has many components: Entity: That is the person, location, or anything by it canstore the data. Attribute: It is the characteristic of the entity. Relationship: It is the associationamong the entities. Cardinality: It is the Constraint in the ERM, among the entities. Thedevelopment steps of the ERM are the following:1.Identify the Entities: We suppose that we have in this Government agency that is theHiring Agency, and this has in its database the entities: Management, Employee,Department, and Customer. Then we can implement these entities by the ERM as thefollowing: Entity by the Rectangle figure.2.Determine the relationships: There are many relationships among the entities:MANAGEMENT manages EMPLOYEE.MANAGEMENT responsible of DEPARTMENT.MANAGEMENT hires CUSTOMER.EMPLOYEE works by MANAGEMENT.EMPLOYEE part of DEPARTMENT.EMPLOYEE manipulates with CUSTOMER.After determining the relationships, it must draw them with all the lines between the entities andthe relationships, by the ERM: (Relationship by the Diamond figure).3.Determine the relationship type (1:1), (1: M), or (M: N). Every relationship type has aspecific symbol to implement it. For example One manager manages many employees: (1:M): We can implement this relationship as the following: One and only one manager canmanage one or many employees.
Assignment 4: Database Modeling and Normalization34.The end figure is the following: