MIS 322: ERD Exercises Student Name:____________________ Assume that at Pine Valley Furniture each product (described by Product No., Description, and Cost) is comprised of at least three components (described by Component No., Description, and Unit of Measure) and components are used to make one or many products (i.e., must be used in at least one product). In addition, assume that components are used to make other components and that raw materials are also considered to be components. In both cases of components being used to make other components, we need to keep track of how many components go into making something else. Draw an E-R diagram for this situation and place minimum and maximum cardinalities on the diagram. A software training program is divided into training modules, and each module is described by module name and the approximate practice time. Each module sometimes has prerequisite modules. Model this situation of training programs and modules with an E-R diagram. Each semester, each student must be assigned an adviser who counsels students about degree requirements and helps students register for classes. Students must register for classes with the help of an adviser, but if their assigned adviser is not available, they may register with any adviser. We must keep track of students, their assigned adviser, and with whom the student registered for the current term. Represent this situation of students and advisers with an E-R diagram. Study the E-R diagram of Figure 7–20. Based on this E-R diagram, answer the following questions: How many PROJECTs can an employee work on? What is the degree of the Includes relationship? Are there any associative entities on this diagram? If so, name them. How else could the attribute Skill be modeled? Is it possible to attach any attributes to the Includes relationship? Could TASK be modeled as an associative entity?
MIS 322: ERD Exercises Student Name:____________________ Assume that at Pine Valley Furniture each product (described by Product No., Description, and Cost) is comprised of at least three components (described by Component No., Description, and Unit of Measure) and components are used to make one or many products (i.e., must be used in at least one product). In addition, assume that components are used to make other components and that raw materials are also considered to be components. In both cases of components being used to make other components, we need to keep track of how many components go into making something else. Draw an E-R diagram for this situation and place minimum and maximum cardinalities on the diagram. A software training program is divided into training modules, and each module is described by module name and the approximate practice time. Each module sometimes has prerequisite modules. Model this situation of training programs and modules with an E-R diagram. Each semester, each student must be assigned an adviser who counsels students about degree requirements and helps students register for classes. Students must register for classes with the help of an adviser, but if their assigned adviser is not available, they may register with any adviser. We must keep track of students, their assigned adviser, and with whom the student registered for the current term. Represent this situation of students and advisers with an E-R diagram. Study the E-R diagram of Figure 7–20. Based on this E-R diagram, answer the following questions: How many PROJECTs can an employee work on? What is the degree of the Includes relationship? Are there any associative entities on this diagram? If so, name them. How else could the attribute Skill be modeled? Is it possible to attach any attributes to the Includes relationship? Could TASK be modeled as an associative entity?
participation_-_erd.docx