我在书籍和作者之间有很多关系。
如何获得作者不止一个的所有书籍？ （在下面的示例数据库中，该值为0）
图书表：
+--------+------------------+
| BookId | Book |
+--------+------------------+
| 1 | Wizard of Oz |
| 2 | Huckleberry Finn |
+--------+------------------+
作者表：
+----------+------------------+
| AuthorId | Author |
+----------+------------------+
| 1 | Mark Twain |
| 2 | Lyman Frank Baum |
+----------+------------------+
连接表：
+--------+----------+
| BookId | AuthorId |
+--------+----------+
| 1 | 2 |
| 2 | 1 |
+--------+----------+
最佳答案
您可以按人数使用分组
select books.* from books
inner join junction on books.id = junction.bookid
group by bookId
having count(distinct AuthorId ) > 1