Abstract: A hardware and/or software (e.g., a controller and/or firmware or software) that monitors a remaining capacity of a battery and adjusts a continuum of system performance settings ranging from best performance to best energy efficiency. The controller starts with best performance setting (at the expense of energy efficiency), and then the controller gradually shifts toward energy efficiency setting (at the expense of performance) when a battery usage exceeds a pre-defined drain rate (e.g., there is a deficit in the battery remaining capacity until the next charge). The controller reverts from energy efficiency setting towards high performance setting when the battery drain rate or discharge rate slows down (e.g., there is a surplus in the battery remaining capacity until the next charge).

Abstract: A method may comprise receiving a template query and one or more keywords from a user, generating a SQL query specification based on the template query and the one or more keywords, formulating SQL code based on metadata specification, sending the SQL code to a query execution engine, receiving correlated query results from multiple physical databases and providing the query result to the user.