Re: [eclipselink-users] JPQL does not do cascading delete

[Tom Ware <tom.ware@xxxxxxxxxx>]

Within the confines of the JPA spec, your two options are the ones you have 
likely already discovered.

1. Read the objects and delete them individually (by iterating, for instance)

2. Run a set of Delete and Update queries to fix relationships

EclipseLink provides some other options

1. You can enable cascading at the database level if your database permits it 
and tell EclipseLink about it and EclipseLink will handle that

2. We have some EclipseLink specific APIs that will delete collections of 
objects (however for the most part, these just do the iteration for you)

3. EclipseLink allows stored procedure calls.  You could do your deletes in a 
stored procedure.

-Tom

On 13/10/2011 12:04 PM, Warren Tang wrote:
> Hi, Tom
>
> Thanks for the info.
>
> I think I can iterate through each record and delete one by one, but the
> performance is a big concern.
>
> Are there other options? I'm a JPA beginner so I would really appreciate it if
> you could elaborate.
>
> Regards,
> Warren Tang <http://blog.tangcs.com>
>
> On 10/13/2011 11:44 PM, Tom Ware wrote:
> > Hi,
> >
> > From the JPA spec:
> >
> > "A delete operation only applies to entities of the specified class and its
> > subclasses. It does not cascade to
> > related entities."
> >
> > And:
> >
> > "Bulk update maps directly to a database update operation, bypassing
> > optimistic locking checks. Portable
> > applications must manually update the value of the version column, if desired,
> > and/or manually validate
> > the value of the version column."
> >
> > Bottom line, you have to manage relationships and locking when you using bulk
> > delete. The reason is that in order for us to manage relationships, we have to
> > have read the entities already and know what the relationships are. This
> > statement goes directly to the DB and may delete entities that have not been
> > read.
> >
> > -Tom
> >
> > On 13/10/2011 11:39 AM, Warren Tang wrote:
> > > t does not do cascading de
> > _______________________________________________
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>
>
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