我如何处理HQL，多对多？ [英] How do I do with HQL, many to many?

问题描述

这里是我的数据库结构。关系很多。我想挑选一些写过同一本书的作者。用SQL，我做到了。我该怎么做与HQL？

Here is my database structure. Relation many to many. I want to make a selection of authors who have written the same book. With SQL, I did. How do I do with HQL?

   Query query = session.createSQLQuery("SELECT FirstName, LastName FROM authors, books, author_book as ab WHERE ab.authorID=authors.authorID AND ab.bookID = books.bookID AND ab.bookID = :id");
   query.setInteger("id", 1);
   List list = query.list();
   Iterator<Object[]> iter = list.iterator();
   while (iter.hasNext()) {
       Object[] obj = iter.next();
       System.out.println(obj[0] + " " + obj[1]);
    }

推荐答案

假设实体名称是Book和作者，该书有作者属性：

Assuming the entity names are Book and Author and that Book has authors attribute:

select a.firstName, a.lastName from Book b join b.authors a where b.id = :id

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