Question

我正在使用如下所示的选择内部联接。如何获得预期的结果？

这是sql语法：

select tgr.id, tgr.venid, sum(tgrd.qty*tgrd.pri), sum(tgrp.amo)
from tgr inner join tgrd on tgr.id = tgrd.id
inner join tgrp on tgr.id = tgrp.id
where tgr.id = 3
group by tgr.id, tgr.venid
having sum(tgrd.qty*tgrd.pri)-sum(tgrp.amo)>0;

结果：

3 | 1 | 462000 | 262000

但是我期望结果：

3 | 1 | 231000 | 131000

来自3个表的源代码：tgr，tgrd，tgrp

tgr table
id  venid
3   1

tgrd table
id  plu qty pri
3   2   2.7 45000
3   1   7.3 15000

tgrp table
id  type  amo
3   2     0
3   2     131000

任何帮助将不胜感激。

Answer 1

由于从tgr到tgrd和tgrp之间存在多对多关系，因此您需要在JOIN插入表之前执行汇总，否则可以将每个值加倍（或更多）。该查询将为您提供所需的结果：

select tgr.id, tgr.venid, total, amo
from tgr 
inner join (select id, sum(qty*pri) as total
            from tgrd
            group by id) tgrd on tgr.id = tgrd.id
inner join (select id, sum(amo) as amo
            from tgrp
            group by id) tgrp on tgr.id = tgrp.id
where tgr.id = 3
group by tgr.id, tgr.venid
having total - amo > 0;

输出：

id  venid   total       amo
3   1       231000.00   131000

Demo on 3v4l.org

选择内部联接返回错误结果

1 个答案: