Efficient Approximations of Conjunctive Queries
نویسندگان
چکیده
منابع مشابه
On Low Treewidth Approximations of Conjunctive Queries
We recently initiated the study of approximations of conjunctive queries within classes that admit tractable query evaluation (with respect to combined complexity). Those include classes of acyclic, bounded treewidth, or bounded hypertreewidth queries. Such approximations are always guaranteed to exist. However, while for acyclic and bounded hypertreewidth queries we have shown a number of exam...
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ژورنال
عنوان ژورنال: SIAM Journal on Computing
سال: 2014
ISSN: 0097-5397,1095-7111
DOI: 10.1137/130911731