有什么参加请告诉我. [英] what are join tell me please.

问题描述

什么是连接，尤其是为什么我们使用内部连接.

what are join especially why we use inner join.

推荐答案

家庭作业?

用于选择两个或多个表的行，这些表使用一个或多个共享字段组合在一起.

查看Wiki了解更多信息:
http://en.wikipedia.org/wiki/Join_%28SQL%29 [ ^ ]

祝您好运！

Homework?

Used to select rows of two or more tables combined using a shared field or fields that match.

Check the wiki for more info:
http://en.wikipedia.org/wiki/Join_%28SQL%29[^]

Good luck!

Join允许您在单个结果集中查看相关表中的数据.从多个表中检索数据，SQL Server允许您应用联接.

内部联接通过使用公共列上的比较运算符从多个联接表检索记录.当应用内部联接时，仅显示公共列中具有满足联接条件的值的行.两个表中不满足连接条件的行都不会显示.

注意内部联接是默认联接，因此您也可以使用JOIN关键字来应用内部联接.此外，您可以使用内部联接关键字.
参考链接:- MSDN- [内部联接] [

Join allow you to view data from related tables in a single result set. to retrieve data from multiple tables the SQL server allows you to apply join.

An Inner join retrieve records from multiple join table by using comparison operator on a common column. when an inner join is applied, only rows with the values satisfying the join condition in the common column are displayed. Rows in both table that don''t satisfy the join condition are not displayed.

Note An inner join is default join, therefore you can also apply an inner join by using the JOIN keyword. in addition you can use Inner Join keyword.
Reference Link :- MSDN-[Inner JOIN][^]

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