Data Model of FRDB with Different Data Types and PFSQL
نویسندگان
چکیده
One of the disadvantages of the relational model is its disability to model uncertain and incomplete data. The idea to use fuzzy sets and fuzzy logic to extend existing database models to include these possibilities has been utilized since the 1980s. Although this area has been researched for a long time, concrete implementations are rare. Literature contains references to several models of fuzzy knowledge representation in relational databases. One of the early works, the BucklesPetry model (Buckles & Petry, 1982), is the first model that introduces similarity relations in the relational model. This chapter gives a structure for representing inexact information in the form of a relational database. The structure differs from ordinary relational databases in two important AbstrAct
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تاریخ انتشار 2008