Masking query data access pattern in encrypted data

A method for searching in an encrypted database, comprising:

• formulating a search as a conjunct of two or more atomic search queries;
• selecting one of the conjuncts as a primary atomic search query;
• and
• generating search capabilities for a secondary atomic search query using the primary atomic search query and the secondary atomic search query;
• wherein the formulating, selecting and generating steps are performed in accordance with one or more processing devices.

An apparatus for encrypting a database, comprising:

• a memory;
• and
• a processor operatively coupled to the memory and configured to:
• encrypt keywords in the database to obtain encrypted search tags for the keywords;
• generate a table of reverse indices for the encrypted search tags;
• and generate a table of cross keyword indices.

An apparatus for searching in an encrypted database, comprising:

• a memory;
• and
• a processor operatively coupled to the memory and configured to:
• formulate a search as a conjunct of two or more atomic search queries;
• select one of the conjuncts as a primary atomic search query so as to generate search capabilities for a secondary atomic search query using the primary atomic search query and the secondary atomic search query.