Query Processing Over RelationalCross Model in Uncertain and Probabilistic Databases

Abstract

In real world, Database stores the information of object. The management of database system provide to load, access, and manipulate the information. Data stored in database is either certain and uncertain. The certain data are those data whose value is known and fixed. If the certain attribute value is not known, then it will have treated as Null value. The uncertain data is data whose value is unknown and not fixed. Its value is uncertain, and its presence is uncertain. In uncertain databases, for particular attribute value is not known so it will be stored alternatives of value with assurance value. There are many existing real-world applications which required uncertain data with assurance value. There are some existing database management systems developed for UPDB like TRIO, ULDB etc. Each system is designed with own organisation and management strategies for organizing uncertain data and its features is suitable for some applications and has some downside also. The center of attention of the paper is towards a new proposed RelationalCross model for organizing uncertain and probabilistic data into database. It expresses, how different types of queries gets processed and transformed using RelationalCross on uncertain databases