Javadogs,

I've spent some time looking at the semantics of fetch-depth and now agree with the critics of the change that I proposed back in the infamous October 1, 2005 message to the expert group subject: Re: JDO2 §12.7.2: fetch-depth only for "recursive fetch group references"?.

I now believe it's impractical to use fetch-depth to mean the maximum depth of the object graph reachable from the root object(s) field because of several messages sent on the subject by Joerg von Frantzuis, Alexander Bieber, and Marco Schultz.

Briefly, the argument is that if fetch-depth limits the number absolutely, then it's not possible easily to use the fetch-group to add another field to a fetch plan simply by adding a fetch-group that includes that field. Instead, a new fetch-group that changes the fetch-depth must be used. And each new use-case needs to provide a different fetch-depth number if another level of fetching is desired.

I believe that the use of fetch-group to determine whether fields (navigating relationships) are fetched should be natural, and that we should therefore use fetch-depth for its original purpose of limiting recursion.

If you disagree with this position, please reply so we can move forward and define the use of fetch-depth for recursion (as in the original semantics of the attribute).

Thanks,

Craig

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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