Patent ID: 8799677

Claim:
An encrypted search database device which performs searching by using a keyword from a plurality of encrypted and registered document data, comprising: an encrypted search result generating module which generates, for the respective keyword, a search result array as a list of the document data corresponding to the keywords and an initial point array as a list of addresses of first data corresponding to the keyword in the search result array, and generates an encrypted search result array and an encrypted initial point array by encrypting each of those with a given encryption key; an encrypted search result storage module which stores the generated encrypted search result array and the encrypted initial point array; an encrypted database searching module which performs searching by the keyword from the encrypted search result array and the encrypted initial point array by using the keyword and the encryption key; and an encrypted search result adding module which adds contents regarding the document data that is newly registered to the encrypted search result array and the encrypted initial point array, wherein: the encrypted search result adding module includes a search result generating unit which generates a linear list that is a list of the search results containing a specific keyword for the newly registered document data, an initial point information generating unit which generates initial point information that is the address of the first data corresponding to the keyword in the linear list, an initial point information encrypting unit which encrypts the generated initial point information with the encryption key, and adds/stores it to the encrypted initial point array, an encrypted linear list adding unit which generates an encrypted linear list acquired by encrypting the linear list with the encryption key, and adds/stores it to the encrypted search result array; and the encrypted linear list adding unit has a function which stores the respective keyword and the final point information that is the address of the last data in the encrypted linear list for the keyword to an adding information storage module provided in advance as adding information.