exception when changing order of an indexed collection

iterator · **Joined:** Wed Feb 15, 2006 4:47 am **Posts:** 2

Hibernate version: 3.1.1
Database: Mysql 4.1.12a-nt

I have mapped a property to an indexed collection as follows:

Code:

@OneToMany()
@Cascade({CascadeType.ALL, CascadeType.DELETE_ORPHAN})
@IndexColumn(name="position")
public List<Section> getSections() {
   return sections;
}

The indexed collection contains some entities and I want to change the position of an entity by doing the following steps within a transaction:

Code:

Section section = session.get(Section.class, sectionId);
sections.remove(section);
sections.add(newIndex, section)

when committing the following exception is thrown:

Code:

java.sql.BatchUpdateException: Duplicate entry '3' for key 2

Do I use a wrong method to change the position of an entity in an indexed collection?
What would be the correct way to change positions?
Or is it even impossible to do it in only one transaction?

kgignatyev · **Posted:** Thu Feb 16, 2006 7:50 pm

Perhaps remove method does not delete element from collection. There might be vwrious reasons for that, but the net result is that there are two "identical" elements in the collection.

TOMBATLECRUISEr · **Joined:** Tue Nov 29, 2005 12:31 pm **Posts:** 75

Hi,

Post your mappings. How is the collection managed ? Provide some additional details (but no more than 15-20 lines).

iterator · **Joined:** Wed Feb 15, 2006 4:47 am **Posts:** 2

TOMBATLECRUISEr wrote:

Hi,

Post your mappings. How is the collection managed ? Provide some additional details (but no more than 15-20 lines).

I have given the mapping already. It is done with Hibernate Annotations 3.1beta7.

iterator wrote:

@OneToMany()
@Cascade({CascadeType.ALL, CascadeType.DELETE_ORPHAN})
@IndexColumn(name="position")
public List<Section> getSections() {
return sections;
}

This means I have a OneToMany mapping to a collection of Section entities with an index column named position and a cascade ALL that includes even DELETE_ORPHAN.
I don't think that the mapping is the problem but there must be a normal way to do a position change.