The Fixpoint Bounded-Variable Queries are PSPACE-Complete
نویسندگان
چکیده
منابع مشابه
Bounded-Variable Fixpoint Queries are PSPACE-complete
We study the complexity of the evaluation of bounded-variable xpoint queries in relational databases. We exhibit a nite database such that the problem of deciding whether a closed xpoint formula using only 2 individual variables is satissed in this database is PSPACE-complete. This clariies the issues raised by Vardi in Var95]. We study also the complexity of query evaluation for a number of re...
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ژورنال
عنوان ژورنال: BRICS Report Series
سال: 1996
ISSN: 1601-5355,0909-0878
DOI: 10.7146/brics.v3i41.20023