Ahhh... In my conversation with this OpenJPA customer, he had mentioned a "delete orphan" feature. Now I know where the reference came from. Thanks.
Kevin On 3/7/07, Craig L Russell <[EMAIL PROTECTED]> wrote:
For the Hibernate-erati in the audience, this feature (JDO calls it "dependent" and JPA doesn't have it) is called cascade="all-delete- orphan". Craig On Mar 7, 2007, at 6:28 PM, Kevin Sutter wrote: > Thanks, Abe. This explanation helps a great deal. Should we > update the > documentation with some of this information? > > Kevin > > On 3/7/07, Abe White <[EMAIL PROTECTED]> wrote: >> >> First, dependent should be compared to cascade=REMOVE rather than (or >> in addition to) cascade=ALL. >> >> cascade=REMOVE means "when I remove this parent instance immediately >> cascade the remove operation to the referenced instance(s)". It's a >> very simple and naïve implementation and its behavior is mandated by >> the JPA spec. >> >> Dependent means "at the end of the transaction if the referenced >> instance(s) are no longer referenced by this parent and have not been >> assigned to any other parent, remove it/them". It's much smarter / >> more subtle. For example if you null a dependent relation but don't >> delete the parent, the referenced instance(s) will still be deleted >> at the end of the transaction, because they are no longer referenced >> by the parent (unless of course you assign them to some other parent >> in the same transaction). >> >> p.s. Note that dependent != db garbage collection. A dependent >> instance that is severed from its parent is deleted at the end of the >> transaction unless assigned to another instance in the same >> transaction -- we don't search the db to find out if any other parent >> not involved in the transaction references the dependent instance >> before deleting >> it.__________________________________________________________________ >> _____ >> Notice: This email message, together with any attachments, may >> contain >> information of BEA Systems, Inc., its subsidiaries and >> affiliated >> entities, that may be confidential, proprietary, copyrighted >> and/or >> legally privileged, and is intended solely for the use of the >> individual >> or entity named in this message. If you are not the intended >> recipient, >> and have received this message in error, please immediately return >> this >> by email and then delete it. >> Craig Russell Architect, Sun Java Enterprise System http://java.sun.com/products/jdo 408 276-5638 mailto:[EMAIL PROTECTED] P.S. A good JDO? O, Gasp!
