所以这个Report直接使用INNER JOIN或者Left join/Right Join连接两张表都得不到想要的数据。当时Report的开发者的思路是先将符合
使用FULL OUTER JOIN拼接多表数据
[日期：2012-10-19] 来源：Linux社区 作者：SmithLiu328 [字体：]
今天帮用户修改一个报表，里边设计到出库和入库的操作，要将每个产品每天的出入口信息列出来。
可能存在这样的情况：
1. 产品在出库表中存在数据但是入库表中没有数据
2. 产品入库表中存在数据但是出库表中没有数据
所以这个Report直接使用INNER JOIN或者Left join/Right Join连接两张表都得不到想要的数据。当时Report的开发者的思路是先将符合条件的产品从出库表和入库表中找出来，然后使用LEFT JOIN连接入库表和出库表获得最终数据。当然这样做没有问题，但是不需要中间表，只需要借助FULL OUTER JOIN就可以获得需要的数据。（FULL OUTER JOIN平时一般很少用到）
这里我们举个例子：
QTYINT)
QTY
1,10)
2,20)
2,30)
3,40)
--希望得到的最终结果：
BON A.ID= B.ID
BON A.ID= B.ID
BON A.ID= B.ID
BON A.ID= B.ID
UNION
BON A.ID= B.ID
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