Question 1 Given the following business rules, create the appropriate Crow’s Foot ERD. a. A company operates many departments. b. Each department employs one or more employees. c. Each of the employees may or may not have one or more dependents. d. Each employee may or may not have an employment history. Question 2 The Hudson Engineering Group (HEG) has contacted you to create a conceptual model whose application will meet the expected database requirements for the company’s training program. The HEG administrator gives you the description (see below) of the training group’s operating environment.
The HEG has 12 instructors and can handle up to 30 trainees per class. HEG offers five “advanced technology” courses, each of which may generate several classes. If a class has fewer than 10 trainees, it will be canceled. Therefore, it is possible for a course not to generate any classes. Each class is taught by one instructor. Each instructor may teach up to two classes or may be assigned to do research only. Each trainee may take up to two classes per year. Given that information, do the following: a. Define all of the entities and relationships. Question 3 Use the following business rules to create a Crow’s Foot ERD.
Write all appropriate connectivities and cardinalities in the ERD. a. A department employs many employees, but each employee is employed by one department. b. Some employees, known as “rovers,” are not assigned to any department. c. A division operates many departments, but each department is operated by one division. d. An employee may be assigned many projects, and a project may have many employees assigned to it. e. A project must have at least one employee assigned to it. f. One of the employees manages each department, and each department is managed by only one employee. g.
One of the employees runs each division, and each division is run by only one employee. Question 4 3. Automata Inc. produces specialty vehicles by contract. The company operates several departments, each of which builds a particular vehicle, such as a limousine, a truck, a van, or an RV. When a new vehicle is built, the department places an order with the purchasing department to request specific components. Automata’s purchasing department is interested in creating a database to keep track of orders and to accelerate the process of delivering materials. The order received by the purchasing department may contain several different items.
An inventory is maintained so that the most frequently requested items are delivered almost immediately. When an order comes in, it is checked to determine whether the requested item is in inventory. If an item is not in inventory, it must be ordered from a supplier. Each item may have several suppliers. Given that functional description of the processes encountered at Automata’s purchasing department, do the following: a. Identify all of the main entities. b. Identify all of the relations and connectivities among entities. c. Identify the type of existence dependency in all relations.