MySQL 的时间查询语句

1.按天查询数据库中每小时的sql语句

   select sum(kwh) kwh,sum(v) v,sum(a) a ,avg(temp) temp  ,DATE_FORMAT(`monitor_hour`,'%Y-%m-%d %H') from solar_monitor_hour

    where  station_id='1'

    and  monitor_hour >=  '2016-06-30' 

    and   monitor_hour <= '2016-07-03'  

    group by DATE_FORMAT(`monitor_hour`,'%Y-%m-%d %H');

2.按月查询数据当月每天的数据的sql语句

   select sum(kwh) kwh,sum(v) v,sum(a) a ,avg(temp) temp  ,DATE_FORMAT(`monitor_day`,'%Y-%m-%d') from solar_monitor_month

   where  station_id='1'

   and  monitor_day >=  '2016-06' 

   and   monitor_day <= '2016-08'  

   group by DATE_FORMAT(`monitor_day`,'%Y-%m-%d');