Neighborhood/Conceptual Query Answering with Imprecise/Incomplete Data
نویسندگان
چکیده
The evolution of database systems tends to the development of higher degree of user friendliness such that the system can be directly handled by nonprofessionals In order to reach this goal the database system needs to provide a query language by which queries can be speci ed conceptually Also the query condition may be relaxed such that information within a certain semantic distance to the exact answer can be obtained Moreover the real world information is usually imprecise and incomplete It is therefore important to store imprecise and incomplete information in a database and to manipulate this information accordingly In this paper we provide a conceptual query language by which fuzzy query conditions and neighbor hood query conditions can be speci ed Query processing strategies for these two query conditions are proposed considering imprecise and incomplete information A domain concept hierarchy is constructed on top of a numerical domain to handle imprecise data while dependencies between database attributes are derived for incomplete information An application of the techniques for processing queries under network partitioning is also discussed
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