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From Christiaan <christiaan...@hotmail.com>
Subject Feature request: copy by query
Date Tue, 20 Nov 2007 12:25:13 GMT

Hi,
related to the delete by query (and my post regarding update by query) I
would like to make a request for a copy by query feature. I frequently
encounter situations where large amounts of objects have to be copied. This
usually results in high memory usage since both the original and the copy
have to be completely loaded into memory. This feature would be similar to
the sql insert statement. I am calling this copy since I would like to
stress that it should copy objects which are already in the datastore. The
copy by query should be able to copy these objects without loading them
twice into memory. Of course special action has to be taken when it comes to
dealing with references. May be something similar can be done as with
detachement, but I think it would already be an improvement if the bulk of
the primitive / embedded data can copied and later on the references can be
set programmatically. 

Another nice option would be to be able to copy objects of type B (extends
A) to objects of type C (extends A) for which the newly created C objects
are filled with data from their common ancestor.

kind regards,
Christiaan
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