Device and method for increasing the security of a database

A non-transitory computer-readable storage medium having embedded therein program instructions, which when executed by a processor, causes the processor to execute a method of data processing, the method comprising:

• receiving a query word;
• partitioning the query word to form a plurality of sub-query words based on a length of a sliding window;
• in response to receiving the query word and partitioning the query word, searching a plurality of stored irreversibly encrypted substrings corresponding to the plurality of sub-query words, wherein each of the plurality of stored irreversibly encrypted substrings is associated with a string of reversibly encrypted raw data, and wherein the length of the sliding window is determined based on a collision rate of the plurality of stored irreversibly encrypted substrings;
• and
• in response to searching, outputting one or more of the plurality of stored irreversibly encrypted substrings and the associated string of reversibly encrypted raw data corresponding to the plurality of sub-query words as a query result.

A data device, comprising:

• a memory that stores instructions and data in a data structure;
• and
• a processor coupled to the memory, the processor to:
• receive a query word;
• partition the query word to form a plurality of sub-query words based on a length of a sliding window;
• in response to the receipt of the query word and the partitioned query word, search a plurality of stored irreversibly encrypted substrings corresponding to the plurality of sub-query words, wherein each of the plurality of stored irreversibly encrypted substrings is associated with a string of reversibly encrypted raw data, and wherein the length of the sliding window is determined based on a collision rate of the plurality of stored irreversibly encrypted substrings;
• and
• in response to the search, output one or more of the plurality of stored irreversibly encrypted substrings and the associated string of reversibly encrypted raw data corresponding to the plurality of sub-query words as a query result.