Linear Constraint Databases
نویسندگان
چکیده
k Abstract. We give an AC 0 upper bound on the complexity of rst-oder queries over (innnite) databases deened by restricted linear constraints. This result enables us to deduce the non-expressibility of various usual queries, such as the parity of the cardinality of a set or the connectivity of a graph in rst-order logic with linear constraints over the reals.
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تاریخ انتشار 2007