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@inproceedings{DBLP:conf/sigmod/GuptaMR95,
author = {Ashish Gupta and
Inderpal Singh Mumick and
Kenneth A. Ross},
editor = {Michael J. Carey and
Donovan A. Schneider},
title = {Adapting Materialized Views after Redefinitions},
booktitle = {Proceedings of the 1995 ACM SIGMOD International Conference on
Management of Data, San Jose, California, May 22-25, 1995},
publisher = {ACM Press},
year = {1995},
pages = {211-222},
ee = {http://doi.acm.org/10.1145/223784.223817, db/conf/sigmod/sigmod95-16.html},
crossref = {DBLP:conf/sigmod/95},
bibsource = {DBLP, http://dblp.uni-trier.de}
}
We consider applications using materialized views, and add a twist to the view maintenance problem - what if the view definition itself changes. Can we do better than recomputing the view from the base relations by adapting the materialized view instead? Traditional view maintenance tries to maintain the materialized view in response to modifications to the base relations; we try to ``adapt'' the view in response to changes in the view definition.
Such techniques are needed for applications where the user can change queries dynamically and see the changes in the results fast. Data archeology, data visualization, and dynamic queries are examples of such applications.
We consider all possible redefinitions of SQL Select-From-Where-Groupby, Union, and Minus views, and show how these views can be adapted using the old materialization for the cases where it is possible to do so. We also identify extra information that can be kept with a materialization to facilitate a redefinition. This paper is comprehensive in considering all possible changes to the view definition. Changes in the Select, From, Where, and Groupby clauses can be handled, as can changes in the operands to the Union and Except operations. We also handle multiple simultaneous changes to a view without necessarily materializing intermediate results. We identify guidelines for users and database administrators that can be used to facilitate efficient view adaptation.
Copyright © 1995 by the ACM, Inc., used by permission. Permission to make digital or hard copies is granted provided that copies are not made or distributed for profit or direct commercial advantage, and that copies show this notice on the first page or initial screen of a display along with the full citation.
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,
SIGMOD Record 24(2),
June 1995