You have been hired by the sales department of ABC Manufacturing. Mark Harris, the sales manager has requested that you develop an ER model for his customer relationship management (CRM) system that he is proposing. The requirements for the database are:
- The model must store mailing and contact information for all clients.
- The clients may have multiple contacts.
- Each of these contacts may have a different address.
- The model must store short description of each e-mail, conversation, or mailing to each client.
- The model must attach the client to the assigned sales person.
Harris believes four entities are required to accomplish the above tasks.