SQL Server:联接表时删除重复的列 [英] SQL Server : removing duplicate column while joining tables

问题描述

我有4个表，其中一列在所有表上都通用.有没有一种方法可以创建一个视图，在该视图中我可以按同一列连接所有表，而我只能看到一次公共列.

I have 4 tables with one column is common on all tables. Is there a way to create a view where I can join all tables by same column where I see the common column only once.

假设我有table1

Let's say I have table1

Cust ID | Order ID | Product_Name

表2

Cust_ID | Cust_Name | Cust_Address

表3

Cust_ID | Cust_Acc | Acc_Type

表4

Cust_ID | Contact_Phone | Cust_Total_Ord

这是我用来联接表的代码；

Here is the code I use to join tables;

SELECT * 
FROM table1
LEFT JOIN table2 ON table1.Cust_ID = table2.Cust_ID
LEFT JOIN table3 ON table2.Cust_ID = table3.Cust_ID
LEFT JOIN table4 ON table3.Cust_ID = table4.Cust_ID

我将所有表连接在一起，从每个表中看到Cust_ID，如下所示；

I get all tables joined by I see Cust_ID from each table as below;

Cust ID| Order ID|Product_Name| Cust_ID| Cust_Name|Cust_Address| Cust_ID| Cust_Acc| Acc_Type|Cust_ID|Contact_Phone|Cust_Total_Ord

是否可以删除重复的Cust_ID列，还是需要在SELECT中写入每个列的名称?我总共有50列以上，因此很难全部编写.

Is there a way to remove duplicate Cust_ID columns or do I need to write each column name in the SELECT? I have more than 50 columns in total so will be difficult to write all.

对不起，如果这是一个非常愚蠢的问题，我已经检查了以前的类似问题，但无法弄清楚，谢谢您的帮助.

Sorry if it is a really dumb question, I have checked previous similar questions but couldn't figure out and thanks for help.

推荐答案

您在所有表上都有公共列，因此可以使用using(common_column)删除重复的列.

your have common columns on all tables so could use using(common_column) to remove duplicated columns.

SELECT * 
FROM table1
LEFT JOIN table2 using(Cust_ID)
LEFT JOIN table3 using(Cust_ID)
LEFT JOIN table4 using(Cust_ID)

我希望那很有用.

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