从一个表中获取数据,通过MYSQL中的其他表对其进行过滤[复制]

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Table 1:

userid name
1      Dharam
2      James
3      Ramesh
4      David

Table 2:

follower(id) following(id)
1            2
2            1
2            3
3            4

Here, I have Table 1 for all users and Table 2 for who is following whom.

I want to get result as

Show the users from 'Table 1' WHERE 'Table 1' users should not be already following the same person

Means, Get users whom user 1 is not following FROM Table 1 filtered by Table 2

Result:

3
4
</div>

Use: inner query

SELECT * from users WHERE user_id NOT IN (
               SELECT user_id_foreign_key FROM follow_details)

Or you can do it with a join:

 SELECT t1.userid, t2.follower
 FROM tbl1 AS t1 
      LEFT JOIN tbl2 ON t1.userid = t2.follower
 HAVING follower IS NOT NULL