View Management in Distributed Data Base Systems
نویسندگان
چکیده
The structure of data to be stored by a Data Base Management System (DBMS) is usually decided by a database administrator. Individual users and applications are generally interested in only a subset of the data stored in the database. Often, they wish to see this subset structured in a way which reflects their particular needs. Since it is not generally possible to structure a database so as to please aU of its users, some mechanism is needed whereby each user can view the data according to his (her) own requirements. The representation of the data structure as seen by a user is often referred to as an external schema; the view mechanism is a means by which a DBMS can support various external schemas.
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