The study of databases began with the design of efficient storage and data sharing techniques for large amount of data. This paper concerns the processing of imprecision and indiscernibility in relational databases using vague rough technique leading to vague rough relational database model. We utilize the notion of indiscernibility and possibility from rough set theory coupled with the idea of...

We present a framework for studying the concept of independence in a general context covering database theory, algebra and model theory as special cases. We show that well-known axioms and rules of independence for making inferences concerning basic atomic independence statements are complete with respect to a variety of semantics. Our results show that the uses of independence concepts in as d...

1. Introduction We suggest here a methodology for updating data-The ability of the database user lo modify the con-bases with integrity constrain& and rules for deriving inex-tent of the database, the so-called updale operation, is fun-plicit information. First we consider the problem of damental to all database management systems. Since updating arbitrary theories by inserting inu, them or del...

Ensuring high quantity and quality of water for humans is becoming more important because the supply risks in extreme climates. With increasing urbanization, urban resource management increasingly important. The hydrologic analysis pipelines can help decision-makers understand pressure, flow rate, quality, possible leakages, extending feasible strategies sustainable development smart cities. In...

Functional dependencies [4] and multivalued dependencies [5,11] are important, widely-studied constraints on databases. A fundamental issue in database theory is the question of determining whether or not a given set of dependencies (in our case, functional and multivalued dependencies) logically implies another given dependency. We provide a simple and elegant set-theoretic characterization fo...

Constraints define the world we live in. Database systems manage data about a domain of interest in our world. Hence, effective data management requires data to satisfy the constraints that define the domain of interest. In practice, most database systems adopt the industry standard for managing data, i.e. the Structured Query Language (SQL). In theory, constraints have mostly been investigated...

Classical database systems have been introduced in the late 50’s and have proved their usefulness in various domains. However, their incompetence to deal with vague and imprecise information, has lead to new data base designs. On the other hand the use of linguistic terms has also shown its usefulness. The assignment of linguistic terms to phenomena in order to describe the characteristics or p...

Classical database systems have been introduced in the late 50's and have proved their usefulness in various domains. However, their incompetence to deal with vague and imprecise information, has lead to new data base designs. On the other hand the use of linguistic terms has also shown its usefulness. The assignment of linguistic terms to phenomena in order to describe the characteristics or p...