sql – 内部连接的对面

内部联盟的对立面是什么？对于表表Person(int PersonId,varchar PersoName,int AddrId),我想知道Person中具有不良地址表中没有行的错误AddrId的行.

解决方法

What will be the opposite of inner join?

一个OUTER加入,可以有三个选项：

>左
>右
>满

This is a good visual representation of JOINs

I want to know the rows in Person with bad AddrId which don’t have a row in the Address table.

使用LEFT JOIN / IS NULL

SELECT p.*
     FROM PERSON p
LEFT JOIN ADDRESS a ON a.addrid = p.addrid
    WHERE a.addrid IS NULL

使用NOT EXISTS

SELECT p.*
  FROM PERSON p
 WHERE NOT EXISTS(SELECT NULL
                    FROM ADDRESS a
                   WHERE a.addrid = p.addrid)

使用NOT IN

SELECT p.*
  FROM PERSON p
 WHERE p.addrid NOT IN (SELECT a.addrid
                          FROM ADDRESS a)

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