Something like this is available in postgres, mssql, etc and is called a "materialized view" [0]. In the postgres case, you have to update the materialized vie

Something like this is available in postgres, mssql, etc and is called a "materialized view" [0]. In the postgres case, you have to update the materialized view manually, but in the mssql case, the updates are done automatically when the origin data is updated. [0] - http://en.wikipedia.org/wiki/Materialized_view http://en.wikipedia.org/wiki/Materialized_view