php - PHP MYSQL 反面选择

Question

$line = @mysql_query("SELECT * FROM clips, userclips 
WHERE userclips.userid='$id' AND 
userclips.clipid=clips.id ORDER BY clips.title");

它返回与特定用户关联的所有剪辑。但是，我很难编写一个完全相反的查询；选择与该用户无关的所有剪辑。

我试过这个：

$line = @mysql_query("SELECT DISTINCT * FROM clips, userclips 
WHERE userclips.userid!='$id' AND userclips.clipid=clips.id ORDER BY clips.title");

确实会返回与该用户无关的剪辑，但它会丢失与任何用户无关的剪辑。

如果可以的话请帮忙 ：）

Answer 1

 $line = @mysql_query("SELECT DISTINCT * FROM clips WHERE clips.id 
 NOT IN (SELECT clipid FROM userclips WHERE userid='$id') ORDER BY clips.title");

Answer 2

返回与特定用户无关的所有剪辑和用户信息，其 id 已传递

SELECT * FROM clips, userclips 
WHERE userclips.userid!='$id'
ORDER BY clips.title

Answer 3

我将使用 not in 进行此类查询

Select * 
From clips 
Where id NOT IN  (SELECT clips.id 
                  FROM clips, userclips 
                  WHERE userclips.userid = '$id' 
                    AND userclips.clipid = clips.id 
                  ORDER BY clips.title)