关键词: 粗糙关系数据库（RRDB）, 近似度量, 精确度量

Abstract: The accurate and approximate measures of rough functional dependency are proposed in this paper in order to find potential and interesting patterns for rough relational database.The approximate measure of functional dependency for classical relational database and its properties are reviewed，then the accurate and approximate measure of rough functional dependency are introduced，moreover their formalization definitions are given，as well as the basic property with which accurate and approximate measure satisfied are investigated，and the example for related formulae are given.The introduction of approximate theory of rough functional dependency will accelerate the development of knowledge discovery for rough relational database and extend its research field.

Key words: Rough Relational Database（RRDB）, approximate measure, accurate measure