It is common in real life to find fuzzy information that comes from subjective judgments or the imprecision in measured data. Fuzzy approaches have been used to extend database systems in storing and updating imprecise information (data) and in processing imprecise queries. Consider a fuzzy query: find name, grade of quite good students and just tall students where age > 15. This query includes...

Users often have vague or imprecise ideas when searching the databases and thus may not know how to precisely formulate queries that lead to satisfactory answers. Based on the fuzzy set thoery, this paper proposes a fuzzy query approach which can support the expression of fuzzy queries and translate the fuzzy query into the precise query in order to provide relevant answers to the users. The fu...

-The traditional query in relational database is unable to satisfy the needs for dealing with fuzzy linguistic values. In this paper, a new data query technique composed of fuzzy theory and MS-SQL is provided. Here, the query can be implemented for fuzzy linguistic variables query via an interface to Microsoft ASP.NET. It is being applied to an realistic instance i.e. questions could be express...

Two fuzzy database query languages are proposed. They are used to query to fuzzy databases that are enhanced from relational databases in a way that fuzzy sets are allowed in both attribute values and truth values. A fuzzy calculus query language is constructed based on the relational calculus and a fuzzy algebra query language is also constructed based on the relational algebra. In addition, t...

ÐIn a fuzzy relational database where a relation is a fuzzy set of tuples and ill-known data are represented by possibility distributions, nested fuzzy queries can be expressed in the Fuzzy SQL language, as defined in [25], [23]. Although it provides a very convenient way for users to express complex queries, a nested fuzzy query may be very inefficient to process with the naive evaluation meth...

The image data as well as the nature of querying image data is fuzzy. Users like to retrieve images based on similarity rather than exact matching. Often, the users are able to provide only partial information while posing queries. As a consequence, the query languages of traditional databases which deal with precise data are inappropriate for querying image data. Content based retrieval system...

Expression and processing of vagueness, which has many real world applications, is not handled effectively in the conventional relational model. In this paper we investigate a fuzzy extension to the relational data model and propose three fuzzy relational query languages. ‘ho of them are the Level-l Fuzzy Relational Algebra and Level-l Fmzy Relational Calculus. They are fundamental query langua...

ABSTRACT Many real world problems involve imprecise and ambiguous information rather than crisp information. Recent trends in the database paradigm are to incorporate fuzzy sets to tackle imprecise and ambiguous information of real world problems. Fuzzy query processing in multidatabases have been extensively studied, however, the same has rarely been addressed for fuzzy multidatabases. In this...

ln a fuzzy relational database where a relation is atuzzy sel of tuples and ill-known data are represented by possibility distributions, nested fuzzy queries can be expressed in lhe Fuzzy SQL language, as defined in [25], [23]. Although it provides a very convenient way for users to express complex queries, a nested fuzzy query may be very inefficient to process with the naive evaluation method...