MySQL的从另外一张表update多个字段到另外一张表中去

2014-11-24 18:41:08 · 作者: · 浏览: 0

例如: 把表 tk_zyt_scenery_order的 字段更新到 t_advs_order中去, 一般可能会这样写:


UPDATE t_advs_order SET


attribute1=(SELECT o.order_state FROM tk_zyt_scenery_order o WHERE o.order_id=`on`),


attribute2=(SELECT o.order_state FROM tk_zyt_scenery_order o WHERE o.order_id=`on`)


WHERE EXISTS (SELECT o.order_state FROM tk_zyt_scenery_order o WHERE o.order_id=`on`);


这样效率比较低下, 优化写法:


UPDATE t_advs_order a INNER JOIN tk_zyt_scenery_order s ON s.order_id=a.`on` SET


a.attribute1=s.order_id,


a.attribute2=s.order_id;