本文介绍了SQL Server外连接的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
1。是否真的可以说Full Outer Join总会返回与Left或Right Outer Join相同的行数？
2.完全外部用于你不知道（也不关心）两个表中哪一行有更多行的情况？相反，你需要所有匹配和不匹配的行吗？
3.或者当你必须外连接多个表（超过两个）时，Full Outer更有意义）？
1. Is it true to say that a Full Outer Join will always return the same amount of rows as either a Left or Right Outer Join?
2. Would a Full Outer to be used in situations where you didn't know (nor care) which of the two tables had the more rows? where instead you need all matching and non-matching rows regardless?
3. Or do Full Outer's make more sense when you have to outer join multiple tables(more than two)?
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