Review Figure 2-8 and Figure 2-22. a. Identify any attributes in Figure 2-22 that might...

Composite attribute:

• A composite attribute can be easily split into several small components. The partial identifiers are added to the attribute in a strong entity to make a full attribute.

• Composite attribute contains meaningful component parts.

• For example:

o Communication address is a composite attribute; an address may be a combination of multiple address lines.

Multi-valued attribute:

• Multivalued attribute is an attribute that can have more than one value in its entity instance.

• For example:

o A person is a multivalued attribute; a person may know one or more language.

a. Composite attribute:

• From the given ER-diagram in the book, it has been noticed that Salesperson LName, Salesperson MI, and Salesperson FName are the composite attributes of the SalspersonName, but it is not mentioned in the book ER-diagram for the SALESPERSON entity type.

• Customer Street, Customer City, and Customer State are the composite attribute of the Customer Address attribute that is not found in the book ER-diagram for the CUSTOMER entity.

• Vendor Street, Vendor City, and Vendor State are the composite attribute of the Vendor Address attribute that is not found in the book ER-diagram for the VENDOR entity.

• The Employee LName, Employee MI and Employee FName are the composite attributes of the Employee Name attribute that is not found in the book ER-diagram for the EMPLOYEE entity.

The modified ER-Diagram of the Pine Valley Furniture Company with composite attributes:

• The given ER-diagram in the book has been modified and redrawn with the composite attribute in the tables SALESPERSON, CUSTOMER, VENDOR, and EMPLOYEE.

b. Multi-valued attribute:

• From the given ER-diagram in the book, the multivalue attribute the Product Finish has been noticed in the PRODUCT entity.

o There will be more than one Product Finish. This will affect the price of the PRODUCT.

The modified ER-Diagram of the Pine Valley Furniture Company with multi-valued attributes:

• The given ER-diagram in the book has been modified and redrawn with the multi-valued attributes in the entity PRODUCT.

c.

Yes, it is possible to use the same attribute as both the composite and multi-value attributes.

• For example consider an attribute CUSTOMER in the given ER-diagram.

o The Customer Name, Customer Street, Customer City, Customer State, and Customer Postal Code are the composite attributes of the Customer ID attribute in the CUSTOMER entity.

o A customer may or may not have more number of addresses. Hence the CUSTOMER entity is also having multivalue attributes.