#上个月的第一天
select date_sub(date_sub(date_format(now(),'%y-%m-%d'),interval extract(
day from now())-1 day),interval 1 month);
select UNIX_TIMESTAMP(date_sub(date_sub(date_format(now(),'%y-%m-%d'),interval extract(
day from now())-1 day),interval 1 month))
#上个月的最后一天:
select date_sub(date_sub(date_format(now(),'%y-%m-%d'),interval extract(
day from now()) day),interval 0 month) as date;
select UNIX_TIMESTAMP(date_sub(date_sub(date_format(now(),'%y-%m-%d 23:59:59'),interval extract(
day from now()) day),interval 0 month)) as date;
#获取当月最后一天
select last_day(curdate());
#获取本月的第一天
select date_add(curdate(),interval -day(curdate())+1 day);