sql - 帮助创建一个相当复杂的sql语句

Question

大家好，我不太确定如何用 google 搜索的形式来描述它，所以我决定来这里看看你们是否可以提供帮助。基本上，我想知道如何将以下伪 SQL 转换为实际的 mysql 查询:

Select one random row 
  from `posts` 
 where (the user's id, which is supplied by the script) is not found in the `votes` table 
        with a post id of (the selected post's id).

如能提供帮助，万分感谢。

Answer 1

像这样:

SELECT *
FROM Posts
WHERE Posts.ID NOT IN (
    SELECT Votes.PostID FROM Votes WHERE Votes.UserID=@UserID
)
ORDER BY Rand()
LIMIT 1