联接的SQL Server问题 [英] Sql Server Problem for Join

问题描述

嗨
先生，当我编写带有内部联接的查询时，我遇到了一个问题，它给出了多行，例如如果我在两个表上都有2行，那么它给出了4行数据，如何减少仅两行帮助我

Hi
sir i have a problem when i write a query with inner join then it gives multiple rows like if i have 2 rows on both table then it gives 4 rows data how to reduce only two rows help me

推荐答案

使用一些主键比较可以在where子句中达到完美的条件.

use some primary key comparsion make a perfect condition in where clause.

亲爱的达摩德拉(Dear Dharmendra)，
首先，您应该提供查询的完整详细信息.

在这里，您必须使用带有右表和左表的列的一些比较来编写具有``ON''子句的内部联接的查询，例如

如果我有Product和ProductInfo表，并且有一个ProductID，则分别是主键和参考键.因此我的查询将如下所示.

从P.ProductID = Pi.Productid上的Product P内部联接ProductInfo Pi中选择*

Dear Dharmendra ,
First,You should give full details of your query.

here u have to write query with inner join having ''ON'' clause using some comparison of column for right and left table , for e.g.

If i have Product and ProductInfo tables and there is a ProductID is primary key and reference key resp. so my query would be like as following.

select * from Product P inner join ProductInfo Pi on P.ProductID=Pi.Productid

首先，您应该提供查询的完整详细信息.

请参阅下面的链接
http://msdn.microsoft.com/en-us/library/aa213234％28v = sql.80％29.aspx [ ^ ]

First,You should give full details of your query.

refer below link
http://msdn.microsoft.com/en-us/library/aa213234%28v=sql.80%29.aspx[^]

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