基于商用数据库管理系统的字符串数据的加密存储与查询

在非可信环境下对数据进行加密是保护数据库中数据安全的一种有效方法，但如何对加密数据进行高效地查询是一个难点，引起了研究界的重视．本文提出加密字符数据的一种存储结构，除了加密数据以外，还以加密的方式存储了原始数据的特征值，并基于这种结构实现了对加密数据的两阶段查询方法，通过实验证明其性能较先解密后查询的方法有较大的提高．

Storage and Query over Encrypted String Based on Commercial Database Management System

Database encryption has become an important mechanism of securing data stored in database in the non-entrusted environments. However, people must sacrifice functionality to ensure security because encryption and decryption great degrade query performance. To solve such a problem, a way of implementing SQL query on encrypted string data is proposed. When string data are stored in encrypted database, it not only stores encrypted string data, but also turns string data into characteristic values through using characteristic functions and store characteristic values as additional columns in the encrypted table. When querying data, it applies a way of two-phase query. Results of experiments validate the functionality and usability of our approach.