Technical Interview Questions and Answers :: DBMS
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It is a particular property, which describes the entity.
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A relation Schema denoted by R(A1, A2, …, An) is made up of the relation name R and the list of attributes Ai that it contains. A relation is defined as a set of tuples. Let r be the relation which contains set tuples (t1, t2, t3, ..., tn). Each tuple is an ordered list of n-values t=(v1,v2, ..., vn).
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It is the number of attribute of its relation schema.
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It is an association among two or more entities.
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The collection (or set) of similar relationships.
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Relationship type defines a set of associations or a relationship set among a given set of entity types.
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It is the number of entity type participating.
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A database schema is specified by a set of definitions expressed by a special language called DDL.
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It specifies user views and their mappings to the conceptual schema.
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This language is to specify the internal schema. This language may specify the mapping between two schemas.