what is attributes and explain.[DBMS-2]

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Attribute 

-Properties or character of the entity is called attribute
 the attribute are the descriptive properties 
 proceed by the each member of the entity set 
-ex The possible attribute of the customer entity are customer city, customer id, loan.
\-There are 4 types of the entity :
                                                     -single value and multi value attributes 
                                                     -simple and composite attributes
                                                     -derived attributes 
                                                     -null attributes

single value attributes:

In the single value attributes there are the value for the specific entity.

multi value attributes:

In the multi value attributes there has a set of value for a specific entity.
ex: 

simple attribute:

It can,t be divided into two sub parts.
ex:

composite attributes:

The composite attribute which is composed of more than one values.
ex:


Derived attributes:

-Derived attribute the value for derived attribute can be derived from the value of the other related attributes and entity.
-the value of the related attributes is known as base attribute/stores attributes.
ex:


null  attributes:

which entity no attribute is known as null attributes

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