Re: makePersistent detached instance deleted on database

[Craig L Russell]

Hi Joerg,

On Mar 8, 2006, at 6:10 PM, Joerg von Frantzius wrote:

Craig L Russell schrieb:

Hi Erik,

When you invoke makePersistent on a detached instance, the instance must exist in the database. You don't insert it at commit. [..]

Does that mean that makePersistent() must not insert detached instances for which it cannot find an object in the datastore?

Yes.

In 12.6.7 it has "For a detached instance, they [the methods makePersistent() and makePersistentAll()] locate /or create a persistent instance/ with the same JDO identity as the detached instance, and merge the persistent state of the detached instance into the persistent instance."

I'm asking because our replication algorithm relies on that.

Good.

Also I find it confusing that the method most prominently used for inserting new objects shouldn't do so for detached instances.

Regards,

Craig

There is a bunch of history that you should look at, most of which is in the jdo-dev archives. Bottom line, we used to have a different API, attachCopy, but we looked at what it had to do for transient and detached instances and decided that it wasn't worth making a different API for attaching detached instances.

Craig

On Mar 8, 2006, at 7:14 AM, Erik Bengtson wrote:

Hi,


instead of reinserting it for a second time. Is that right?

Maybe this can be clarified in the spec.

Regards,

What happens when we invoke makePersistent on a detached instance that was deleted by another isolated process? I suspect that we raise an exception

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!

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!

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