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entity is a thing in the real world with an independent existance. and entity set is collection or set all entities of a particular entity type at any point of time.
take an example:
a company have many employees ,and these employees are defined as entities(e1,e2,E3....) and all these entities having same attributes are defined under ENTITY TYPE employee.and set{e1,e2,.....} is called entity set.
we can also understand this by an anology .
entity type is like fruit which is a class .we havn't seen any "fruit"yet though we have seen instance of fruit like "apple ,banana,mango etc.hence..
fruit=entity type=EMPLOYEE
apple=entity=e1 or e2 or e3
enity set= bucket of apple,banana ,mango etc={e1,e2......}
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β 13y ago
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