Explain different types of attribute with example and their symbols used in ER diagram.

Explain different types of attribute with example and their symbols used in ER diagram.
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1 Answer

Answer :

Different types of attributes are:

1. Simple attribute: A simple attributes are those which cannot be subdivided. Eg:Rollno– 

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2. Composite attribute: a composite attribute is that which can be subdivided Eg: name – can be divided into first_name, middle_name and last_name 

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3. Single valued attribute- an attribute which can have only one value for an entity. Eg:ssc_per 

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4. Multivalued attribute - an attribute that can take more than one value for an entity. Eg:phoneno

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5. Derived attribute - an attribute for which the value can be calculated or determined from another attribute Eg: age from dateofbirth 

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