Question

Define entity and entity type and entity set

Answer 1

Entity
It is something which has real existence. Like tuple1 contains information about Ram(id, name and Age) which has existence in real world . So the tuple1 is an entity. So we may say each tuple is an entity.
Entity Type
It is collection of entity having common attribute. As in Student table each row is an entity and have common attributes. SoSTUDENTis an entity type which contains entities having attributes id, name and Age.Also each entity type in a database is described by a name and a list of attribute.So we may say a table is an entity type
Entity SET
It is a set of entities of same entity type. so a set of one or more entities of Student Entity type is an Entity Set.

Answer 2

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