mysql 如果存在B表 则更新A表某个状态
update c_prods p set p.is_dangerous = 1 where p.cas in (select t.cas from (select cas from c_dangerous limit 0,500)as t)
其实我一直在你身边
update c_prods p set p.is_dangerous = 1 where p.cas in (select t.cas from (select cas from c_dangerous limit 0,500)as t)