Some Fuzzy Logic Based Approaches to Flexible Database Querying and their Use for Discovering Security Related Information

摘要

We are concerned with the browsing of numerical data stored in popularrelational databases by querying those data repositories using some non-standard,human consistent querying tools that fall within a broad category of flexible queries.We present queries with linguistic quantifiers and bipolar queries which can helpexpress a real human intention which crucial because information that can suggesta security threat concerns a sophisticated concept and is related to a sophisticatedcombination of values of attributes that is difficult to express by using traditionalquerying tools, and also terms in those representations concern mostly issues andaspects which are difficult to precisely specify and quantify, and hence tools offuzzy logic are employed. We assume a numerical relational database. Some veryspecific combination of values of attributes can suggest a potentially dangerous sit-uation. To retrieve information the user has to express his or her interest, intentionor information needs as a query. Usually, resulting query criteria cannot imply abinary decision of the acceptance/rejection of a row, and a degree is employed. Aflexibility is obtained by a fuzzy modeling of linguistic terms and a non-standardaggregation of elementary conditions in a query, in our case a user may be fullysatisfied with, e.g., most of them being fulfilled, also with varying importances,which results in queries with linguitsic quantifiers. We also discuss another non-standard approach to flexible querying that involves a specific flexible aggregationscheme assuming two types of conditions within a query, so called bipolar queriesinvolving mandatory (required) and to some extent optional (desired) conditions.