The demand of storing and processing data online grows quickly to adapt to the rapid change of business. It could lead to crisis if the cloud service provider is compromised and data of users are exposed to attackers in plaintext. In this paper, we introduce a practical scheme that dynamically protects and outsources data on demand, as well as propose a corresponding architecture to securely process data in Database Service Provider. After studying over 1300 database models, we believe this scheme can be applied in production with justifiable result.