A set of entities with the same attributes is called

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A set of entities with the same attributes is called entity type. All entities in an entity type share common characteristics. It is known as entity class . For Example: STUDENT entity class is a set of all students. Similarly, BOOK entity type is a collection of all books etc. Ms Mehwish
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8 Entities Instance An entity instance is the single occurrence of entity type Each entity instance of an entity type has its own value for each instance. For Example: A student Ali of STUDENT entity type is an entity instance. Ms Mehwish
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9 Entity Set A set of all entities of a particular entity type in the database at a given point of time is called an Entity Set. For Example: An entity set Student may consist of all students in the university. Another entity set Teacher may consist of all teachers in the university etc... The same name is usually used for both entity type and entity set . For example BOOKS refers to both a entity type and as well as the current set of all books in the database.
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