Technical Note: BIRN-DI-TN-2003-01 Query Containment, Minimization, and Semantic Optimization of Conjunctive Queries (or: More on Uncles and Aunts)
نویسنده
چکیده
This technical note presents the ubiquitous problem of query containment for conjunctive queries (an NP-complete problem), and an elegant implementation CQCP of Conjunctive Query Containment in Prolog, in just 7 lines of code. We also describe two important applications of conjunctive query containment: semantic query optimization and minimization. The latter can be implemented by another concise Prolog algorithm, requiring additional 7 lines of code . . .
منابع مشابه
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