查询两次执行。 [英] Query Twice Execution.

问题描述

我执行  3个表（收据，项目和付款）的联合查询，其中收据表是主要表格而物品&付款表有收据的外键，没有自己的主键。 

I execute  a joint query for 3 tables (Receipt, Items and Payment) where Receipt table is primary table While Items & Payment table have foreign keys to Receipt without any Primary Keys of their own. 

问题是当我尝试获取数据时，查询执行两次ID，其中我有两行以上在商品和付款表中。

The problem is when I try Fetching data the query executes twice for an ID where I got more then two rows In Items and Payment Tables.

查询是 

SELECT     收据。*，项目。*，付款。*
$
FROM       收据INNER JOIN

                     收据上的项目.RID = Items.RID INNER JOIN

                     在Receipt.RID = Payment.RID付款

SELECT     Receipt.*, Items.*, Payment.*
FROM        Receipt INNER JOIN
                      Items ON Receipt.RID = Items.RID INNER JOIN
                      Payment ON Receipt.RID = Payment.RID

在你们问之前;为什么我要单独付款表？

Before You guys ask; why did I separate Payment table?

这是因为可能会因为积分而分期付款。

It's because There might be Installments due to credits.

Habib Ur Rehman

Habib Ur Rehman

推荐答案

可能是因为一对多的关系？

Probably because a relationship one-to many?

对于一张收据 你可以有很多物品和很多款项，对吗？

For one receipt  you can have many items and many payments, am I right?

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