Conjunctive Query Containment in the Presence of Disjunctive Integrity Constraints
نویسندگان
چکیده
This paper considers the problem of containment of conjunctive queries CQ with disjunctive integrity constraints Query containment problem in the pres ence of integrity constraints has been studied broadly especially with functional and inclusion dependencies However to handle incomplete information in the database disjunctions are needed to be expressed as integrity constraints In this paper we introduce disjunctive referential integrity constraints and give a sound and complete algorithm for checking the containment of conjunctive queries under disjunctive referential and implication constraints
منابع مشابه
Conjunctive Query Containment in the Presence of Disjunctive Integrity Constraints (extended Abstract)
This paper considers the problem of containment of conjunctive queries (CQ) with disjunctive integrity constraints. Query containment problem in the presence of integrity constraints has been studied broadly, especially with functional and inclusion dependencies. However, to handle incomplete information in the database, disjunctions are needed to be expressed as integrity constraints. In this ...
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