Hi,

I have a problem with cascading delete.

I have a set of tables that are linked with bidirectional many-to-one/one-to-many, like this:

<class name=A table=A>
...
<set name="B" lazy="false" inverse="true" cascade="all">
<key column="b"/>
<one-to-many not-found="ignore" class="B"/>
</set>
</class>

<class name="B" table="B">
...
<many-to-one name="A"
column="a"
class="A"
lazy="false"
cascade="all"
/>
</class>

I would like any entry of B referenced by a certain entry in A to be deleted when the entry of A is deleted, but not the other way around (deleting an entry of B shouldn't delete any entries of A). At the moment this works the exact opposite, it cascades from B to A, but when i delete an element in A that is connected to an entry in B, i get the following error message:

javax.servlet.ServletException: org.hibernate.exception.ConstraintViolationException: could not delete: [xxx.persistence.persistentclasses.A#32768]
org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:515)
org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:422)
com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:129)
com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77)
org.apache.struts2.dispatcher.ActionContextCleanUp.doFilter(ActionContextCleanUp.java:99)
org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)

root cause

org.hibernate.exception.ConstraintViolationException: could not delete: [xxx.persistence.persistentclasses.A#32768]
org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:96)
org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:2710)
org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:2893)
org.hibernate.action.EntityDeleteAction.execute(EntityDeleteAction.java:97)
org.hibernate.engine.ActionQueue.execute(ActionQueue.java:273)

I have tried with different values for cascade and inverse, with no appearant difference. What am i doing wrong here?

- Tobb

Set the inverse property of your OneToMany to false!
This way the collection which is currently handled by B objects will be handled by the parent A object.

And modify the Cascade.ALL from the ManyToOne to Cascade.MERGE (or any other Cascade Type that doesn't include Cascade.DELETE depending on your requirements)