您好，我有下表，我想选择每个月插入的最大值(计数(*))。sqlfiddle.com/#!2/13036/1select*frombroadcastprofile,plugged,company,tstamp1,2,1,2013-10-0108:20:001,3,1,2013-10-0108:20:002,1,1,2013-10-0108:20:002,3,1,2013-10-0108:20:003,1,1,2013-10-0108:20:003,1,1,2013-09-0108:20:00所以如果我做类似下面的事情:selectplugged,count(*),extract(mon