Mapping-equivalence and oid-equivalence of single-function object-creating conjunctive queries
نویسندگان
چکیده
منابع مشابه
Equivalence and Minimization of Conjunctive Queries
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The problems of query containment and equivalence arefundamental problems in the context of query processingand optimization. In their classic work [2] published in1977, Chandra and Merlin solved the two problems for the language of conjunctive queries (CQ queries) on relationaldata, under the “set-semantics” assumption for query evalu-ation. Alternative semantics, called ba...
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ژورنال
عنوان ژورنال: The VLDB Journal
سال: 2016
ISSN: 1066-8888,0949-877X
DOI: 10.1007/s00778-016-0421-x