@ManyToMany association's schema breaks ManyToMany

lally · **Joined:** Mon Mar 05, 2007 5:21 am **Posts:** 4

Hi everyone. This one's been a thorn in the side for quite some time, so any help (or pointers to a good book! JP with Hibernate isn't doing it for me) would be really appreciated.

Hibernate v.3.2.1 GA.

Code:

@ManyToMany
@org.hibernate.annotations.CollectionOfElements
@JoinTable(
   name="QuestionGroup_Question",
   joinColumns={@JoinColumn(name="QGROUPNAME_ID", referencedColumnName="id", unique=false)},
   inverseJoinColumns={@JoinColumn(name="Q_ID", referencedColumnName="id", unique=false)}
   )
@IndexColumn(name="ORDER_IDX", base=1)
List<Question> questions = new ArrayList<Question>();

The problem is, this is the generated MySQL schema:

Code:

mysql> describe QuestionGroup_Question ;
+---------------+------------+------+-----+---------+-------+
| Field         | Type       | Null | Key | Default | Extra |
+---------------+------------+------+-----+---------+-------+
| QGROUPNAME_ID | bigint(20) | NO   | PRI |         |       | 
| Q_ID          | bigint(20) | NO   | UNI |         |       | 
| ORDER_IDX     | int(11)    | NO   | PRI |         |       | 
+---------------+------------+------+-----+---------+-------+
3 rows in set (0.03 sec)

Specifically, Q_ID has to be unique!! It's essentially a many-to-one, and I don't know what's causing it.

Does anyone see anything wrong with my annotations? Or is there something else I should add? Is there another way to specified an ordered many-to-many that's worked for anyone?

Any help would be really appreciated. Thanks in advance!