Containment of inequality queries revisited
نویسندگان
چکیده
The study of the containment of conjunctive queries containing inequalities (denoted inequality queries in this paper) was a thoroughly studied and long standing problem. In [3], we offered an exact condition, along with a procedure, to test query containment of this type of queries, using the idea of canonical databases. In this work, we present a different approach that is sensibly more efficient, based on the idea of testing query containment by using the theory of subsumption of formulas.
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تاریخ انتشار 2002