View Updates in Stratiied Disjunctive Databases*
نویسندگان
چکیده
منابع مشابه
Disjunctive Deductive Databases : Semantics , Updates , and Architecture ?
The basic assumption in relational and deductive databases is that there are no gaps in our knowledge. That is, the database cannot store data that contain null values or data that is indeenite. In practical situations knowledge is not precise, and there are gaps in our knowledge. These gaps may be due to null values in the data, may arise when we combine several databases that lead to inconsis...
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View update problem in deductive databases is concerned with the translation of an update of an intensional relation by modifying the underlying relations of the extensional part of the database. In the existing algorithms for view updates of a deductive database, a sound and complete proof procedure is usually employed to generate explanations for the atom to be inserted or deleted. In the cas...
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Active knowledge bases result from the addition of action rules to ordinary knowledge bases, like relational or deductive databases and their (for instance, disjunctive) extensions. Action rules provide, e.g., for knowledge base updates on certain conditions, thus beeing able to enforce integrity constraints. But they can also call procedures, like running certain diagnostic tests, or turning s...
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In this paper, we study the problem of incremental maintenance of materialized views when the view deenitions are allowed to contain: (a) constraints, and (b) well-founded modes of negation. A materialized view in our framework consists of a set of constrained non-ground tuples. We develop incremental algorithms to compute such non-ground materialized well-founded views, extending previous resu...
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تاریخ انتشار 1998