| 摘要 |
<p>An encrypted database system or the like, which make it possible to perform linking between a plurality of tables without decrypting them and further to reduce a risk of the data correlation leaking out, is provided. A client terminal (10) encrypts an inputted first table having data in a-th and b-th columns and an inputted second table having data in c-th column by the use of a secret key stored in advance and outputs the encrypted first and second tables to an encrypted database server (50), and sends a partial link command to perform linking between the encrypted first and second tables in terms of data having a value q in the a-th column using the b-th and c-th columns as keys, to the encrypted database server (50), along with a search key generated from the secret key. The encrypted database server (50) receives and stores the encrypted first and second tables, extracts data having a value q in the a-th column from each of the encrypted first and second tables by the use of the secret key, performs linking together the extracted pieces of data using the b-th and c-th columns as keys, and sends back a result of the linking.</p> |
