Abstract: The increasing energy consumption of IT system makes us take energy efficiency into consideration when designing a new generation of DBMS.Because SQL queries consumes almost 70%~90% of the database resources,the energy efficiency of database can be improved by optimizing query and energy consumption modeling.After an in-depth study on optimization of query processing mechanism,an energy consumption model for SQL was proposed and many experiments were designed on a series of query optimization methods to show their effectiveness of performance improvement and energy reduction.Experiments and energy consumption data analysis prove that CPU utilization is the most critical factor that affects power consumption,SQL energy consumption optimization can ignore the memory optimization and should balance two aspects:performance optimization and power consumption optimization,and the model and the proposed methods have good application value.

Key words: Green computing,SQL energy consumption optimization,SQL energy consumption modeling,Query processing