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Traditional databases use only crisp data and are only capable of manipulating them using Boolean logic, while in reasonable number of situations we are faced with uncertain, approximate and vague data. In those situations it may not be possible to transform these data into crisp forms. Fuzzy relational database management systems (FRDMS), on the other hand, are capable to store and retrieve both, crisp and non-crisp data and to manipulate them using fuzzy logic. This paper proposes a possibility based fuzzy relational database management system. Mechanisms to design and implement the database is shown and query processing methods are described. Fuzzy queries are first translated into SQL, and passed to MS-SQL server to process it. The result is then fuzzified. A user can express his (her) request using linguistic terms and can choose different retrieval threshold values. The system is then used to store information about patients whose bone density is measured for diagnosis of osteroporosis. The system showed to be more flexible and produces more accurate results.