Hi Jason, the author Brett Slatkin and others:

1) For the list property, the video shows simple example of standard 1:n
Message Receivers in python and Java. It then demonstrates a very
efficient technique of Message and MessageIndex with the query of
MessageIndex in python (NO Java from then on). I look at both the low
level datastore with Query.setKeyOnly() and the query "select id from"
to get the results of List<Key>, then go through the loop to get the
receivers. I may miss something, since the python code looks so clean.
But once you are in any environment, it is very expensive to switch.
This technique has major impact in data modeling.

2) Again for the set intersection, the python code looks so clean. I
roughly sketch what need to be done on the Java side with either low
level of datastore or with JDO. It is still not elegant as the shown
codes. The demos are also in python. Again, the technique of merge join
will have very significant impact on data modeling that GAE may surpass
other platforms.

Haven't put enough time in it yet, I wonder if any one has worked out
the demos in Java and suggested best practices in data modeling for a
complex large application. The job Brett Slatkin sets out to do has not
completed without the Java codes since GAE now supports Java.

Thanks
Duong BaTien
DBGROUPS and BudhNet


On Tue, 2010-01-12 at 14:13 -0800, Jason (Google) wrote:
> Can you be more specific about what you're trying to accomplish so we
> don't have to search through the video to find what you're looking
> for? Or, at least provide a timeline reference that we can refer to in
> the video. :)
> 
> 
> Thanks,
> - Jason
> 
> On Mon, Jan 11, 2010 at 7:29 AM, Duong BaTien <[email protected]>
> wrote:
>         Hi:
>         
>         Is there any blog and/or note to apply list properties and
>         merge-join in
>         python as in the following talk and demos
>         
> http://code.google.com/events/io/2009/sessions/BuildingScalableComplexApps.html
>  using Java and JDO?
>         
>         Thanks
>         Duong BaTien
>         DBGROUPS and BudhNet
>         
>         
>         
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