Based on Rough Set
An Qiusheng,Xu Jiucheng,Wang Guoyin,Shen Junyi
(School of Electronics and Information Engineering,Xi'an Jiaotong Univercity 710049,China)
Abstract:Based on RRDM(Rough Relational Database Model), a querying theory of RRDB (Rough Relational Database) is analyzed through decomposition principle, projection principle, definability of RRDB and lower approximation and upper approximation. A new querying method based on RRDB querying theory, rough data querying of RRDB is presented. The rough data querying is classified into three kinds: crisp querying, rough complete querying and rough combinatorial querying. In addition, the rough data querying is discussed through three aspects and some computational simulation is performed. The simulation results show the feasibility and correctness of the proposed method.
Keywords:RRDB;rough data querying;rough complete querying;rough combinatorial querying;crisp querying