Exposing the vagueness of query results on partly inaccessible databases

Oliver Haase, Andreas Henrich
2001 Proceedings of the tenth international conference on Information and knowledge management - CIKM'01  
Query processing on partly inaccessible databases generally does not yield exact, but vague result sets. A good notion of vague sets fulfills two aims: It keeps the degree of vagueness of the query result as small as possible, and it clarifies the degree of and the reasons for the vagueness to the end user. The first goal requires a good internal representation, while the second goal requires a good external representation of a vague set. In this paper, we present a novel calculus for
more » ... vague sets that meets both requirements. This is the first approach that is well suited for both internal and external representation of vagueness induced by partial inaccessibility. It consists of a data representation that is capable of holding all the necessary information. Complementary, we have accordingly adapted the usual query language operations. These adaptations are independent of a concrete query language, to make them applicable to most existing query languages. The adapted operations minimize the vagueness of the result, propagate the reasons of uncertainty of the individual vague candidates, and compute an expressive description of the missing elements.
doi:10.1145/502585.502595 dblp:conf/cikm/HaaseH01 fatcat:52zafkrmzvcudiqsra6sqplmju