Revise the ER diagram drawn in the previous exercise to include the following mandatory attributes:

QUESTION:

Revise the ER diagram drawn in the previous exercise to include the following mandatory attributes: CLIENT– ID number, name, address (city, state, zip), phone number(s), birthdate; AGENT – agent number, name, phone number, area; and commission received by an agent for selling a Policy to a client?

SOLUTION:

On this exercise, what we were really looking for was how the student handled the commission attribute. Note that commission is defined as “commission received by an agent for selling a Policy to a client. As a product of the relationship between a CLIENT and an AGENT, the commission should be shown as an attribute of the relationship type Policy. Since the cardinality ratio is m:n, it cannot be shown as an attribute of the agent. However, had commission been defined as simply an annual percentage of sales that an agent receives for a given period based on performance, then it would be an attribute of AGENT.