JPQL問題解決查詢中要比較的集合的節點

我有一個圖書實體，它具有設置爲文檔實體的OneToMany關係。換句話說，在Hibernate中，我的book實體返回一個文檔列表作爲屬性文檔。JPQL問題解決查詢中要比較的集合的節點

我想返回尚未分配給書籍的用戶的文檔列表。這裏是我的JPQL查詢，我已經finagled它的每一個方式，我可以，我不能得到它的工作：

select d from Document d WHERE d.user = :user 
AND NOT EXISTS(SELECT b.docs from Book b WHERE b.docs = d)

凡書是一個實體，用戶是通過一個實體，b.docs是文件清單，文件（d）是實體。

我在做什麼錯？與查詢的這個特殊的版本，我收到了錯誤：

org.hibernate.TypeMismatchException: left and right hand sides of a binary logic operator were incompatibile [java.util.Collection(com.fallenjusticestudios.bardwalk.model.Book.docs) : com.fallenjusticestudios.bardwalk.model.Document]

書：

@Entity 
@Table(name="book") 
public class Book { 

    @Id 
    @GeneratedValue(strategy=GenerationType.AUTO) 
    private Long id; 

    @Column 
    @NotEmpty 
    @NotNull 
    private String title; 

    @Column 
    @NotEmpty 
    @NotNull 
    private String description; 

    @ManyToOne(cascade=CascadeType.MERGE, targetEntity=User.class) 
    @JoinColumn(name="user") 
    private User user; 

    @OneToMany(cascade=CascadeType.MERGE, fetch=FetchType.LAZY, targetEntity=Document.class) 
    @JoinColumn(name="document_id",referencedColumnName="id") 
    private List<Document> docs; 


    // Will need to add Contest to the fields later on. 
    // 
    // 


    public Long getId() { 
     return id; 
    } 

    public String getTitle() { 
     return title; 
    } 

    public String getDescription() { 
     return description; 
    } 

    public User getUser() { 
     return user; 
    } 

    public List<Document> getDocs() { 
     return docs; 
    } 

    public void setId(Long id) { 
     this.id = id; 
    } 

    public void setTitle(String title) { 
     this.title = title; 
    } 

    public void setDescription(String description) { 
     this.description = description; 
    } 

    public void setUser(User user) { 
     this.user = user; 
    } 

    public void setDocs(List<Document> docs) { 
     this.docs = docs; 
    } 





}

UPDATE：

闖闖：

查詢：

select d from Document d WHERE d.user = :user 
AND NOT EXISTS(SELECT Document from Book.docs b WHERE b.id = dn.id)

org.hibernate.hql.ast.QuerySyntaxException: Book.docs is not mapped [select d from com.fallenjusticestudios.bardwalk.model.Document d WHERE d.user = :user AND NOT EXISTS(SELECT Document from Book.docs b WHERE b.id = dn.id)]

UPDATE2：

我想通了。我正在討論所有錯誤的查詢。解決方案查詢是：

select d from Document d WHERE d.user = :user 
AND NOT d IN(SELECT d from Book b, IN(b.docs) bd WHERE bd.id = d.id)

來源

2012-03-03 Kyle Richter

我想通了。我正在討論所有錯誤的查詢。解決方案查詢爲：

select d from Document d WHERE d.user = :user 
AND NOT d IN(SELECT d from Book b, IN(b.docs) bd WHERE bd.id = d.id)

來源

2012-03-03 19:39:49

JPQL問題解決查詢中要比較的集合的節點

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