Question

In a requirement gathering session, you have made notes while discussing about Suppliers, with a user from procurement team. A business analyst who is working with you looks at your notes and asks you what the terms below mean with respect to Supplier entity. Explain their meaning giving examples.

1. Unique identifier

2. Composite

3. Single vs Multi-valued

4. Derived

Answer 1

1. Unique Identifier: A unique Identifier is the numerical or alphanumeric pattern unique for each product so that it could be easily identified. Example: Barcode given on the product is the unique identifier.

2. Composite: Composite are the attributes that is made up of more than one attributes. Example: Complete Address of the consumer may contain Adress Line 1 and Address Line 2.

3. Single vs Multi-Valued: Single-Valued attributes are the attribute that contains single attribute. Example: House No. Whereas Multi-Valued attributes are the attributes that contains more than one same attributes. Example: a person may have more than one Phone number.

4. Derived: A derived attribute is the attribute that does exist in physical database but can be derived or calculated when needed. Example: Calculating the percentage of the students whose marks is in the physical database.