A company keeps track of its departments, employees and mobile numbers assigned to employees by the department. Draw an ER diagram using the (min,max) notation for structural constraints, given that: An employee has a unique id, name and can have more than one address A department has a unique id, name and one address A mobile is identified by its number An employee must work in one department only A department has a minimum of 4 employees A department can own up to 10 mobiles An employee can be assigned up to 2 mobiles State any assumptions you make.

Determine the highest normal form (1NF, 2NF, 3NF, or BCNF) for each one of the following six relations. Notice that the primary key of each relation is underlined.) 1 2 3 4 5 6 Relations Work (EmpNumber, ProjectNumber) Work (EmpNumber, ProjectNumber, ManagerSSN) Given that a project has one manager only. Work (EmpNumber, ProjectNumber, HoursPerWeek) Work (EmpNumber, ProjectNumber, EmpName, Location) Given that a project is located in one location only. Work (EmpNumber, ProjectNumber, Location) Given that a project is located in one location only. Work (EmpNumber, ProjectNumber, Location) Given that a location has one project only. Answers

Explain what the Entity-Relationship model is and how it operates.

Creation of Entity Relationship Diagram Draw the entity relationship diagram (ERD) for this information.