MySQL订单慢查询语句优化求解

Question

SELECT b.goodsid
         , b.skuid
         , b.instate
         , sum(b.num) num
from gt_wh_order a1 left join  gt_wh_orderdetail b on  a1.id = b.orderid
where a1.ordertype = '0'
      and a1.deptid = '001002001001'
      AND b.outstate = '0'
    GROUP BY b.goodsid, b.skuid

该语句执行了大概5s，太就了，希望帮忙看一下

Answer 1

首先确定一下外键对应的字段有没有创建索引。