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mysql的从除此以外一张表update多个字

发布时间: 2012-09-25 09:55:59 作者: rapoo

mysql的从另外一张表update多个字段到另外一张表中去

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;

?

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