QUERY PROCESSING IN PROBABILISTIC DATA BASES Francesco
نویسنده
چکیده
Probabilistic data bases are receiving an increasing interest as probabilistic expert syst ems are succeeding in managing uncertainty in diagnostic applications. Like relationa l data bases, the management of probabilistic data bases raises a lot of computational problems such as query optimization. We present some strategies and algorithms to s olve the problems of data joining and query answering, based on the widely accepted assumption of Òuniversal tableÓ, which means that all data sets (i.e., probability table s) stored in a probabilistic data base are assumed to be projections (i.e., marginals) of a higher-order probability table.
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