Watermarking technique has been widely applied to multimedia data as an effective method for ownership protection.The increasing use of relational databases is creating a similar need for applying this technique to databases in order to associate ownership of these databases with their owners.This paper presents a robust algorithm for embedding a string of bits into a database relation.by improving the current relational database watermarking algorithms.We also show how to adjust parameters according to different robustness and imperceptibility requirements.Using implementations running on Oracle

we demonstrate that the performance of our algorithm allows for its use in real world applications.