Draw an ERD. The database should track work orders and tasks of work orders. The following detailed information requirements should be represented by the ERD.
Information stored about a customer includes a unique customer identifier, a name, and a billing address, which includes street, city, state, and zip.
A work order has a unique work order number, a creation date, a date required, a completion date, and a work address, which includes street, city, state and zip.
Customers submit work orders. Each work order is submitted by one customer only.
A work order is accomplished with a set of tasks. Each task has a unique identifier, a task name, and an hourly rate. Tasks are standardized across work orders so that the same task may be performed on many work orders.
When a work order is submitted, the company decides on which set of tasks needs to be performed. For example, tasks T1, T4, T6 may need to be performed in order to accomplish work order W1. Tasks T2, T5, and T6 may need to be performed to accomplish work order W2. A task can require different number of hours to complete for different work orders. For example, T6 of W1 may take 5 hours to complete while T6 of W2 may take 6 hours to complete. For each task required for a particular work order, the database needs to store the estimated number of hours. When the task is performed for that work order, the database should store the start date, the completion date, and the actual number of hours spent on that task.