Guidelines for Creating a Simple Conceptual Model ERD Entities should be rectangles with the name of the entity inside. Relationships should be diamonds with the verb phrase inside. Cardinality constraints must be placed next to the lines as they connect to the entities as shown below. You do not need to indicate participation constraints in the diagram, but you may if you wish. A single line indicates optional participation, and a double line indicates mandatory participation. Given the following business rules, your ERD should look like the one to the left 1 Writer Creates A writer may create many novels A novel is created by a writer A consumer may buy many novels A novel may be bought by may consumers Consumer Novel Dont forget, the simple conceptual model purposely lacks details that will eventually be required in order to keep the diagram simple Buys