| 摘要 |
This disclosure concerns homomorphic encryption for database querying. Numerical values (FIG. 5) are encrypted using keys (FIG. 6) and random numbers (FIG. 7) to produce a ciphertext. The ciphertext is homoporhic and is comprised of two or more sub-ciphertexts (FIG. 8). Queries based on addition (FIG. 10), average (FIG. 11) and multiplication operations can be performed without decrypting the numerical values relevant to the query. Each sub-ciphertext (FIG. 8) is stored in a single record and in separate attributes. There is disclosed methods of encrypting (402) and decrypting, creating a suitable table (400), querying such a database (412) and updating such a database (408, 410). |
