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Decomposition means dividing a large and complex table into multiple small and easy tables. This removes redundancy, anomalies, and inconsistency in a database. This is the first stage of normalization . Suppose we have a relational schema R, in which we have attributes as given below: A 1 , A 2 , A 3 …………A n So R = {A 1 , A 2 , A 3 …………A n } If we decompose it into small parts then R will be divided into the following parts: R 1 , R 2 ……..Rx These all relational schemas belong to the original one R. R 1 , R 2 ……..R x = R Also, we can write that union of all these subsets belongs to the original set R. R 1 U R 2 U R 3 ……..U R x = R Here R 1 , R 2 ……..R x <= R Also 1<= i <= x      (i= number of relation like 1,2,3…..x) Decomposition is further divided into two parts Lossless and Lossy. Let’s discuss them one by one in detail. Lossless Decomposition Loss means data loss while decomposing a relational table. A lossless decomposition is somewhat in which data i