THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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The benefit of MANDATORY in this example is that it is impossible for the client to get detached Entity issues. The client either has a transaction and therefore gets Entities which are still attached and persistent, or the client would get an exception stating that the use of a transaction is mandatory.
See the Transaction Annotations page for a full description of the available transaction attributes.
Writing a unit test for the example
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