This paper describes an extended relational database model based on probability theory and possibility theory. Fuzzy information and probabilistic information are incorporated into the relational databases
simultaneously to represent fuzzy probability of events in the real-world applications. The tuples in such a relation are associated with a possibility distribution, and their attribute values may be uncertain
and represented by probabilistic distributions. Such relational databases are called fuzzy probabilistic relational databases. The structure of the fuzzy probabilistic relational model is proposed in the paper. On the basis, the primitive and natural join operations of the algebra are developed.