右与右的区别左连接与右连接SQL 中的左外连接
之间的结果有什么区别
- RIGHT JOIN 和 RIGHT OUTER JOIN
- LEFT JOIN 和 LEFT OUTER JOIN
?您能通过一些例子解释一下吗?
What is the difference in results between:
- RIGHT JOIN and RIGHT OUTER JOIN
- LEFT JOIN and LEFT OUTER JOIN ?
Can you please explain it through some examples?
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这是一个非常好的视觉解释 通常由我们自己的 Jeff Atwood 进行连接。右外连接与右连接相同,左连接和左外连接也相同。
Here's a very nice Visual Explanation of joins generally by our very own Jeff Atwood. A right outer join is the same as a right join, and left join and left outer join are also the same.
?没有区别。
没有区别。
简而言之,
OUTER
关键字是可选的。您可以包含或省略它,而不会影响结果集。No difference.
No difference.
Simply put, the
OUTER
keyword is optional. You can include it or omit it without affecting the resultset.RIGHT JOIN
和RIGHT OUTER JOIN
之间没有区别。两者是相同的。这意味着 LEFT JOIN 和 LEFT OUTER JOIN 是相同的。SQL 连接的可视化表示
There is no difference between
RIGHT JOIN
andRIGHT OUTER JOIN
. Both are the same. That means thatLEFT JOIN
andLEFT OUTER JOIN
are the same.Visual Representation of SQL Joins
SQL Join 的很好的解释:
参考:链接
Nice explanation of SQL Join:
Reference: link