Question

我有实体：Tweet和User。

Tweet有一个author，它是User类的一个实例。用户正在关注其他用户，并跟踪跟踪他的用户：

@ManyToMany
public List<User> following;

@ManyToMany(mappedBy = "following", fetch = FetchType.LAZY)
public List<User> followedBy;

现在我想加载我正在关注的用户推文。我试过这个：

"FROM Tweet AS tweet " +
                "JOIN tweet.author as author " +
                "JOIN author.followedBy as followedBy " +
                "WHERE tweet.author = followedBy AND ? in followedBy ORDER BY dateCreated DESC"

但它不起作用。我很狡猾的查询。

修改

生成的查询，我从抛出的异常中复制了：

SELECT TWEET0_.ID AS ID10_, TWEET0_.AUTHOR_ID AS AUTHOR4_10_, TWEET0_.CONTENT AS CONTENT10_, TWEET0_.DATECREATED AS DATECREA3_10_ 
  FROM TWEET TWEET0_ 
  INNER JOIN USER USER1_ ON TWEET0_.AUTHOR_ID=USER1_.ID 
    WHERE USER1_.ID IN 
      (SELECT .[*] FROM USER USER2_, USER_USER FOLLOWING3_, USER USER4_ WHERE USER2_.ID=FOLLOWING3_.FOLLOWEDBY_ID AND FOLLOWING3_.FOLLOWING_ID=USER4_.ID AND USER2_.ID=?) 
ORDER BY TWEET0_.DATECREATED DESC LIMIT ?

编辑2

不幸的是，现在我得到了IllegalArgumentException：

    IllegalArgumentException occured : 
org.hibernate.QueryException: illegal attempt to dereference collection [user2_.id.following] with element property reference [id] [select tweet from models.Tweet tweet join tweet.author author where author in (select user.following.id from models.User user where user.id = :id) order by tweet.dateCreated desc]

Answer 1

我在这里使用子查询：

select tweet from Tweet tweet
join tweet.author author
where author in 
(select following.id from User user join user.following following where user.id = :id) 
order by tweet.dateCreated desc

HQL - 需要查询帮助

修改

编辑2

1 个答案: