Answer to Question #246198 in Databases | SQL | Oracle | MS Access for Fred

Question

Production tracking is important in many manufacturing environments (e.g., the pharmaceuticals industry, children’s toys, etc.). The following ER diagram captures important information in the tracking of production. Specifically, the ER diagram captures relationships between production lots (or batches), individual production units, and raw materials.

Answer 1

a) Composite attributes is the type of attribute that contains more than one value. So in the given ERD the composite attributes are:

• 1. ProductType attribute of Production units entity
• 2. type attribute of Raw Materials entity
• 3. ProductDesc attribute of Production units entity
• 4. Create date attribute of Lot entity
• 5. exactWeight attribute of Production units entity

Because

• ProductType attribute and ProductDesc consist of several components of a product.
• type attribute also contains various components like cotton, fabric, poly.
• exactWeight contain weight in pounds and ounces.
• create date consist date and time both.

b) Derived Attribute is the attribute whose value is found/derived from other attributes. So in the given ERD the attribute Cost-of-Materials of Lot entity is acting as a derived attribute because the cost of materials depends on the Unit cost of the raw materials entity attribute.

c) The relationship " raw materials are used in 0..* lots " means that the raw materials exist independently in the system without creating from Lot But if we change the cardinality to "raw materials are used in 1..* lots.” which means there is a need that at-least one lot is required for raw material.