Intelligent unmasking in an in-memory database

A non-transitory computer readable storage medium embodying a computer program for performing a method, said method comprising:

• causing an engine to receive a request for data stored in a first table comprising a masked element including a key and a mask, the masked element corresponding to a plurality of unmasked elements in a database;
• causing the engine to process the first table to create a second table converting the masked element into an element interval indicating a highest level position of the mask;
• causing the engine to create a third table selecting the plurality of unmasked elements sharing the key;
• causing the engine to perform a first join operation of the second table and the third table to create a fourth table including the plurality of unmasked elements sharing the key and falling within the element interval;
• causing the engine to perform a grouping operation of the fourth table to create a fifth table locating a maximum position of the mask with the plurality of the unmasked elements;
• causing the engine to perform a second join operation of the fifth table and the first table to create a sixth table including the plurality of unmasked elements and the key;
• and
• causing the engine to process the request on the sixth table.

A computer system comprising:

• one or more processors;
• a software program, executable on said computer system and embodied upon a non-transitory computer readable storage medium, the software program configured to:
• cause an engine to receive a request for data stored in a first table comprising a masked element including a key and a mask, the masked element corresponding to a plurality of unmasked elements in a database;
• cause the engine to process the first table to create a second table converting the masked element into an element interval indicating a highest level position of the mask;
• cause the engine to create a third table selecting the plurality of unmasked elements sharing the key;
• cause the engine to perform a first join operation of the second table and the third table to create a fourth table including the plurality of unmasked elements sharing the key and falling within the element interval;
• cause the engine to perform a grouping operation of the fourth table to create a fifth table locating a maximum position of the mask with the plurality of the unmasked elements;
• cause the engine to perform a second join operation of the fifth table and the first table to create a sixth table including the plurality of unmasked elements and the key;
• and
• cause the engine to process the request on the sixth table.