Abstract: In recent years, with the growing focus on privacy protection, fully homomorphic encryption (FHE)based encrypted database management systems (DBMS) have gained significant research attention. FHE allows DBMS to be outsourced to cloud servers without revealing plaintext data, preventing internal leaks and external breaches. However, FHEbased DBMS faces challenges such as high computational latency and low query processing capacity. To address these challenges, an efficient ciphertext database system based on Confusion Modulus Component Fully Homomorphic Encryption (CMPFHE) is proposed. This system designs a ciphertext index method that employs  symbolic functions and modulus operations, which reduces computation overhead and improving query efficiency. Additionally, it employs Nvariable Nequation homogeneous equations to achieve rapid ciphertext index retrieval, significantly decreasing the number of operations. This solution performs keyword queries on 10K rows of ciphertext data in just 54 seconds, demonstrating the practical feasibility of fully homomorphic encrypted databases.

Key words: homomorphic encryption, encrypted database, privacy protection, encrypted query, encrypted calculation

摘要： 近年来，随着隐私保护关注度的增加，基于全同态加密(FHE)的加密数据库管理系统(DBMS)受到更多研究关注.FHE允许DBMS外包给云服务器而不泄露明文数据，有效防止内部恶意泄露和外部非法窃取.然而，FHE的DBMS在实际部署中面临高计算延迟和低查询处理能力的挑战.为此，提出一种基于混淆模分量全同态加密算法(CMPFHE)的高效密文数据库系统，通过符号函数与取模运算设计密文索引，降低计算开销，提高查询效率.同时，基于N元N式齐次方程组实现快速密文索引，大幅减少运算次数.该方案在10000行密文数据中进行关键字查询仅需54s，验证了全同态密文数据库的实用性.

关键词: 同态加密, 密文数据库, 隐私保护, 密文查询, 密文计算