Unnesting Fuzzy SQL Queries in Fuzzy Databases
The efficiency of processing fuzzy queries in fuzzy databases is a major concern. We provide techniques to unnest fuzzy queries (of two blocks) of type N, type J, type JA, and nested queries with quantifiers. We show that by unnesting the queries, efficiency can be improved significantly. The results obtained in the paper form the basis for unnesting fuzzy queries of arbitrary blocks in fuzzy databases.
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