google app engine - Can I define a read-only transaction using GAE's JDO? -


I am using the latest version of the GWT GAE w / JDO stack. I have a working queue to update objects with constant data control. I have a live user interface that shows objects to save (without modification).

Looking at tightly defined transactions (start / commit) boundaries, is there a way of defining a read-only transaction for GUI, which does not conflict with the task of updating the object Does it?

I believe they are disputing and throwing these exceptions (abridged) 

 javaax.jdo.JDODataStoreException: org.datanucleus.jdo.NucleusJDOHelper. Transaction back has failed during the commitment on getJDOExceptionForNucleusException (NucleusJDOHelper.java:402) at ORG.datanucleus.jdo. .datanucleus.jdo.JDotransaction.commit (JDotransaction.java:132) .... Nested Treables Staxtress: Java SQL. Cleopation: org.datanucleus.store.appengine.DatastoreTransaction.commit (DatastoreTransaction.java:70)

< P> App Engine Datastore does not really lock (). This means that the transaction which reads only will not interfere or argue in other transactions or transactions that are involved in writing.


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