MyBatis Review——多对多映射

示例：  

              查询用户及用户购置商品信息。

sql语句：

SELECT
	orders.*, USER .username ,USER .sex,
	USER .address,
	orderdetail.id as orderdetail_id,
	orderdetail.items_id,
	orderdetail.items_num,
	orderdetail.orders_id,
	items.`name` items_name,
	items.detail items_detail,
	items.price items_price
FROM
	orders,
	USER,
	orderdetail,
  items
WHERE
	orders.user_id = USER .id
	AND
  orderdetail.orders_id=orders.id
	and 
	orderdetail.items_id=items.id
SEL