select DATE_FORMAT(upload_time，'%Y%u') weeks，count(SN_ID) count from table_sn group by weeks; -- 按照周分组
select DATE_FORMAT(upload_time，'%Y%m%d') days，count(SN_ID) count from table_sn group by days; -- 按照日分组
select DATE_FORMAT(upload_time，'%Y%m') months，count(SN_ID) count from table_sn group by months; -- 按照月分组