Explain view in rdbms, Database Management System

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Explain view in RDBMS?

View - A view is a relation (virtual rather than base) and could be used in query expressions, which is, queries can be written by using the view as a relation. Instead, a view is a named table in which is represented, not through its own physically separate stored data, but through its definition in terms of other named tables (base tables or views). The base relations on that a view is based are sometimes known as the existing relations. The definition of a view in a create view statement is stored within the system catalog. The syntax to create a view is:

CREATE [OR REPLACE] VIEW [()] AS

WITH {READ ONLY|CHECK OPTION [CONSTRAINT

]};


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