Self-Maintainability of Deletions in Conjunctive Queries
نویسنده
چکیده
The topic of materialized view maintenance involves the development of eecient techniques for updating the view when changes are made to the source data from which the views are derived. An important class of materialized views are those which can be maintained without having to access the source data. Such views are called self-maintainable views. In this paper we derive necessary and suucient conditions for a view to be self-maintainable in response to the deletion of tuples from the source data when the view is deened as a conjunctive query.
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