Discuss along with examples about several types of attributes present in the ER model?
Types of Attributes are:
• SIMPLE attributes are attributes which are drawn from the atomic value domains
E.g. Name = {John} ; Age = {23}
• COMPOSITE attributes: Attributes that consist of a hierarchy of attributes
E.g. Address may consists of "Number", "Street" and "Suburb" → Address = {59 + ‘Meek Street' + ‘Kingsford'}
• SINGLE VALUED attributes: Attributes which have only one value for each entity E.g. Name, Age for EMPLOYEE
• MULTIVALUED attributes: Attributes that have a set of values for each entity E.g. Degrees of a person: ‘ BSc' , ‘MIT', ‘PhD'
• DERIVED attributes: Attributes Contain values which are computed from other attributes
Eg. Age can be derived from attribute DateOfBirth. In this situation, DateOfBirth might be known as Stored Attribute