declare startTime VARCHAR(19) default '2014-00-00 00:00:00';
declare tempTime VARCHAR(19) default NOW();
declare endTime VARCHAR(19) default DATE_SUB(tempTime,INTERVAL '3' MONTH); -- 后退三个月时间

DECLARE MonTHSTR VARCHAR(7) default SUBSTR(endTime,1,7);
set endTime=ConCAT(MONTHSTR,'-00 00:00:00');


SELECT startTime as startTime,endTime AS endTime;