What are types of attributes ?, What is the domain of attribute?, What is composite attribute?
An entity is represented by a set of attributes, that is descriptive
properties possessed by all members of an entity set.
Domain – the set of permitted values for each attribute
Attribute types:
- Simple and composite attributes.
- Single-valued and multi-valued attributes
- E.g. multivalued attribute: phone-numbers
- Derived attributes
- Can be computed from other attributes
- E.g. age, given date of birth
Example:
customer = (customer-id, customer-name,
customer-street, customer-city)
loan = (loan-number, amount)
Composite Attribute
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