内外连接的区别 [英] Difference between Inner And Outer Join

问题描述

Helo！



在SQL查询中，内部和外部联接有什么区别？



谢谢！

解决方案

我建​​议你在CP上这篇非常好的文章，它清除了我的思绪....它轻松，易于阅读和清晰。花20分钟潜入，真的值得！

SQL连接的可视化表示 [ ^ ]

谷歌是你的朋友：好好经常拜访他。他可以比在这里发布问题更快地回答问题......



快速搜索 使用您的主题作为搜索词 发出超过一百万次点击： Google内部和外部加入之间的区别 [ ^ ]



将来，请尝试自己做至少基础研究，不要浪费你的时间或我们的时间。

Google资源已经拥有这些SQL命令的功能。它们基本上用于通过基于字段（列）值连接两个（或更多）表来基于列（或两个）从多个表中获取记录。



看看这些在线资源，它们会教你一般关于JOIN，然后阅读INNER和OUTER连接之间的区别。



https://www.mssqltips.com/sqlservertip/1667 / sql-server-join-example / [ ^ ]

https://technet.microsoft.com/en-us/library/ms191472(v = sql.105）.aspx [ ^ ]

SQL Server中的连接类型 [ ^ ]



（将它们置于DESC命令中）首先阅读CodeProject文章，然后参阅TechNet文章。这解释了很多，一般来说，最后转到MS SQL提示上的帖子。您可以随时使用Google来解决此类特定问题，您可以在互联网上找到许多文章，博客和提示。如果需要，您还可以搜索CodeProject目录。 ： - ）

Helo !

In SQL Query What is the difference between Inner and Outer Joins ?

Thanks !

解决方案

I would suggest you this very great article in CP, it cleared my mind.... and it is light, easy to read and clear. Take your 20 Min, to dive into, it is really worth!
Visual Representation of SQL Joins[^]

Google is your friend: Be nice and visit him often. He can answer questions a lot more quickly than posting them here...

A very quick search using your subject as the search term gave over a million hits: Google "difference between Inner and Outer Join"[^]

In future, please try to do at least basic research yourself, and not waste your time or ours.

Google resources already have the functionality of these SQL commands. They are basically used to get records from multiple tables based on a column (or two) by joining two (or more) tables based on a field (column) value.

Have a look at these online resources that will teach you generally about JOINs and then read about the difference between INNER and OUTER joins.

https://www.mssqltips.com/sqlservertip/1667/sql-server-join-example/[^]
https://technet.microsoft.com/en-us/library/ms191472(v=sql.105).aspx[^]
Types of Join in SQL Server[^]

(Put them in a DESC order and) First of all read the CodeProject article first then refer to the TechNet article. That explains a lot, generally, finally move on to the post on MS SQL Tips. You can always Google for such specific questions, there are many articles, blogs, tips already available on internet for you. You can also search CodeProject directory if you want. :-)

这篇关于内外连接的区别的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！