Transparent analytical query accelerator over encrypted data

A computer program product comprising a non-transitory computer-readable storage medium having computer-readable program code embodied therewith, the computer-readable program code configured to be executed by one or more processors of a database system to perform:

• storing a first instance of a first table comprising data in a first database engine in plaintext;
• encrypting at least one predefined column of the first table, resulting in a second instance of the first table containing at least part of the data of the first table in encrypted format;
• storing a second instance of the first table in a second database engine;
• maintaining encryption information about a plurality of encryption methods and encryption keys used for the encryption in the database system;
• receiving a query against the first table;
• determining whether to execute the query in the first database engine on the first table or the second database engine on the second instance of the first table, the determining involving a comparison of the query with the encryption information of the second instance of the first table, the determining resulting in a decision;
• and
• in case of the decision to execute the query in the second database engine, rewriting the query against the second instance of the first table by using at least the encryption information.