Processing Fuzzy SQL Queries with Flat, Context-Dependent and Multidimensional Membership Functions
نویسندگان
چکیده
Analysis of new trends in databases development shows that promising solution in databases gathering a huge quantities of information is approximate retrieval. This work presents the fuzzy queries processing with a special attention to context-dependent and multidimensional membership functions. In the first part, the analysis of occurrence of fuzzy values in SQL queries directed to the databases is shown. Next, the process of interpretation of filtering conditions in SQL queries is discussed and condition on compatibility degree is introduced to SQL queries notation. The main part of the paper describes application of context-dependent and multidimensional membership functions in fuzzy SQL queries as two different approaches, and a whole process of their usage interpretation. All issues considered in this work are illustrated by appropriate examples.
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