select ifnull(b.Total_Qty,0) Total_Qty from check_online_past_12_month_view v
left join (select FROM_UNIXTIME(incoming_date,'%Y-%m') past_month,sum(inspection_qty) Total_Qty from check_online_list t
where FROM_UNIXTIME(t.incoming_date,'%Y-%m')>DATE_FORMAT(date_sub(curdate(),interval 12 month),'%Y-%m')
group by FROM_UNIXTIME(incoming_date,'%Y-%m')) b on v.past_month=b.past_month group by v.past_month;