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ANSWERING SYSTEMS : AN INDISPENSABLE REQUIREMENT FOR SEARCHING IN DATABASES

The conventional relational database management systems (RDBMSs) are not flexible enough to support vague retrieval capabilities directly. That means when available data in a relational database do not match a user’s query precisely, the conventional RDBMSs will only return an empty result set to the user. This limits their applicability to domains where only crisp answers are meaningful. For many other application domains in the commercial world nowadays, however, the users also expect not only crisp results returned but also some other results close to the query in a certain sense. This capability of the applications is particularly very important as well for modern information retrieval systems in the digital age. In this paper, we discuss the lack and the need of supporting vague retrieval capabilities in the existing RDBMSs, introduce some previous prominent researches related to this topic in both the conventional RDBMSs and modern information retrieval systems; and eventually, we will present our most recent achievements in this field as well as introducing topics of interest for future researches.