mysql 跨表更新数据的几种操作

1.

UPDATE product p, productPrice ppSET pp.price = pp.price * 0.8WHERE p.productId = pp.productIdAND p.dateCreated < '2004-01-01'

2.

UPDATE product pINNER JOIN productPrice ppON p.productId = pp.productIdSET pp.price = pp.price * 0.8WHERE p.dateCreated < '2004-01-01'

3.

UPDATE product p
LEFT JOIN productPrice pp
ON p.productId = pp.productId
SET p.deleted = 1
WHERE pp.productId IS null

4.

UPDATE product pINNER JOIN productPrice ppON p.productId = pp.productIdSET pp.price = pp.price * 0.8,p.dateUpdate = CURDATE()WHERE p.dateCreated < '2004-01-01'