Hibernate：选择实体，其中集合包含所有指定的valus

问题描述

我需要帮助一个棘手的hibernate查询问题。我有以下实体：

I need assistance with a tricky hibernate query problem. I have the following entities:

public class Book {
   private String bookId;
   private String author;
   private String isbn;
   private Set<Tag> tags;
   // getters, setters etc.
}

和

public class Tag  {
   private String tagId;
   private String tagName;
  // getters, setters, etc.
}

两者之间的多对多关联，由连接表books_tags_mn与列book_id和tag_id表示。

There is a many-to-many association between the two that is represented by a join table books_tags_mn with the columns book_id and tag_id.

我喜欢做的是以下内容：创建一个hibernate查询/条件查询，返回具有某组标签全部的所有图书。

What I like to do is the following: I want to create a hibernate query/criteria query that returns all book that have all of a certain set of tags. What does work is to select all books that have any of a set of tags.

我一直在使用标准API，但是我已经搞定了一些标准API。没有真正理解它。所以我想要做的（在伪HQL）

I've been messing around with the criteria API but did not truly understand it. So what I am trying to do (in pseudo HQL)

from Book book where book.tags containsAll(:tags)

任何帮助将非常感谢，所以非常感谢你。

Any help on this would be highly appreciated, so thank you very much in advance.

推荐答案

您可以使用以下查询：

select book from Book book
where :numberOfTags = (select count(tag.id) from Book book2
                       inner join book2.tags tag
                       where book2.id = book.id
                       and tag in (:tags))

其中 numberOfTags 是必须匹配的标记集中的标记数。

where numberOfTags is the number of tags in the set of tags that must be matched.

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