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Exercise No. 35: Hertz Car Rental Service (dfm)

This E/R-schema shows the Hertz car rental service.

Cars are rent to customers who can be classified into customer groups (private, business, etc.). There's an option to rent a driver for the car as well. The car is serviced by a garage and belongs to a branch of the Hertz car rental service. This branch is responsible for a certain "renting" area and also belongs to the nationalwide operating Hertz car rental service (parallel hierarchy). The time dimension consists of day and week.

Figure D.E.20.1 - the Hertz car rental service

Please identify the fact of interest and build the attribute tree. No attributes have to be pruned or grafted.

Then derive the fact schema from the tree by defining dimensions, fact attributes and hierarchies and build a glossary for the fact attributes.

Please include an additional fact attribute counting the number of rents.

Solution

Exercises List