Exercise 1 - CARSIdentify all entity types, attributes, relationship types and their degrees in the following case. Hence draw an entity-relationship diagram.An organization makes many models of cars, where a model is characterized by a name and a suffix (such as GL or XL which indicates the degree of luxury) and an engine size.Each model is made up from many parts and each part may be used in the manufacture of more than one model. Each part has a description and an id code. Each model of car is produced at justone of the firm's factories, which are located in London, Birmingham, Bristol, Wolverhampton and Manchester - one in each city. A factory produces many models of car and many types of part although each type of part is produced at one factory only.Exercise 2 - A UNIVERSITYA university consists of several faculties. Within each faculty there are several departments. Eachdepartment may run a number of courses. All teaching staff are attached to departments, each staff member belonging to a unique department. (Note: see how many meanings you can assign to this ambiguous sentence). Every course is composed of subcourses. Some subcourses are part of more than one course. Staff may teach on many subcourses and each subcourse may be taught by a number of staff.Draw an entity-relationship model for this example. Show both cardinalities and optionalities. Put a question mark where the degree is not clear from the text. Don't assume anything; rather, write a list of questions you would have to find answers to to complete the model.Exercise 3 - STUDENTS AND COURSES(Similar to Exercise 2)Draw an entity-relationship diagram for the following scenario, stating any assumptions you findit necessary to make, and showing unknown cardinalities and optionalities using question marks on the relationship line. Show also the attributes explicitly mentioned in the scenario and underline any you consider suitable candidates for being primary keys.
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- Fall '14
- Entity-relationship model, entity