Fuzzy Functional Dependency and Its Application to Approximate Data Querying
نویسندگان
چکیده
I n this paper, we review a new definition of fuzzy functional dependency based on conditional probability and i ts application to approximate data reduction related to operation of projection in classical relational database in order to construct fuzzy integrity constraints [l]. W e introduce the concept of partial fuzzy functional dependency which expresses the fact that a given attribute X does not determine Y completely, but in the partial area of X , i t might determine Y . Finally, we discuss another application of fuzzy functional dependency an constructing fuzzy query relation for data querying and approximate jo in of two or more fuzzy query relations in the framework of extended query system.
منابع مشابه
Project-Join-Repair: An Approach to Consistent Query Answering Under Functional Dependencies
Algebra-based identification of tree patterns in XQuery p. 13 Approximate querying of XML fuzzy data p. 26 Relaxation paradigm in a flexible querying context p. 39 A functional model for data analysis p. 51 Materialization-based range and k-nearest neighbor query processing algorithms p. 65 Flexible querying using structural and event based multimodal video data model p. 75 Reverse nearest neig...
متن کاملMining Full Functional Dependency to Answer Null Queries and Reduce Imprecise Information Based on Fuzzy Object Oriented Databases
Discovery of Full functional dependencies from relations has been identified as an important database analysis technique. In order to deal with information inexactness, fuzzy techniques have extensively been integrated with different database models and theories. However, the information is often vague or ambiguous and very difficult to represent in implementing the application software. This p...
متن کاملA genetic algorithm to discover relaxed functional dependencies from data
Approximate functional dependencies are used in many emerging application domains, such as the identification of data inconsistencies or patterns of semantically related data, query rewriting, and so forth. They can approximate the canonical definition of functional dependency (fd) by relaxing on the data comparison (i.e., by considering data similarity rather than equality), on the extent (i.e...
متن کاملPREDICTING URBAN TRIP GENERATION USING A FUZZY EXPERT SYSTEM
One of the most important stages in the urban transportation planning procedure is predicting the rate of trips generated by each trac zone. Currently, multiple linear regression models are frequently used as a prediction tool. This method predicts the number of trips produced from, or attracted to each trac zone according to the values of independent variables for that zone. One of the main li...
متن کاملAn Extension of Semantic Proximity for Fuzzy Multivalued Dependencies in Fuzzy Relational Database
Following the development of fuzzy logic theory by Lotfi Zadeh, its applications were investigated by researchers in different fields. Presenting and working with uncertain data is a complex problem. To solve for such a complex problem, the structure of relationships and operators dependent on such relationships must be repaired. The fuzzy database has integrity limitations including data depen...
متن کامل