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@inproceedings{DBLP:conf/vldb/BertinoHL83,
author = {Elisa Bertino and
Laura M. Haas and
Bruce G. Lindsay},
editor = {Mario Schkolnick and
Costantino Thanos},
title = {View Management in Distributed Data Base Systems},
booktitle = {9th International Conference on Very Large Data Bases, October
31 - November 2, 1983, Florence, Italy, Proceedings},
publisher = {Morgan Kaufmann},
year = {1983},
isbn = {0-934613-15-X},
pages = {376-378},
ee = {db/conf/vldb/BertinoHL83.html},
crossref = {DBLP:conf/vldb/83},
bibsource = {DBLP, http://dblp.uni-trier.de}
}
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 all 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.
Besides providing users with tailored views of the data the view mechanism contributes to [Chamberlin75]:
In relational DBMS, a view is defined as a "virtual table" derived by a specific query on one or more base tables. The ralational operations join, restrict and project as well as statistical summaries of tables may be used to define a view. Access rights may be granted and revoked on views just as though they were ordinary tables. This allows users to selectively share data, preventing unauthorized users from reading sensitive information.
SQL/DS [SQL81] and INGRES [STonebraker76] are examples of relational DBMS`s that provide the view facility.
In this abstract the implementation of views in distributed relational DBMS`s is discussed. Section 2 briefly reviews view management in a single-site DBMS. In section 3, the view concept is extended to a distributed DBMS (DDBMS) and two types of views are introduced: shorthand views and protecting views. Finally section 4 outlines view management in a DDBMS.
