Consistent Query Answers on Numerical Databases Under Aggregate Constraints
نویسندگان
چکیده
The problem of extracting consistent information from relational databases violating integrity constraints on numerical data is addressed. In particular, aggregate constraints defined as linear inequalities on aggregate-sum queries on input data are considered. The notion of repair as consistent set of updates at attributevalue level is exploited, and the characterization of several complexity issues related to repairing data and computing consistent query answers is provided.
منابع مشابه
The complexity and approximation of fixing numerical attributes in databases under integrity constraints
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