1. A computer-implemented method, comprising: under control of one or more computing systems configured with executable instructions, reading an original data object with a state of â€œunlockedâ€ that is stored in a source data store to obtain substantive data, a version number, and an identifier of the original data object; storing a duplicate data object of the original data object to a destination data store with a state of â€œlocked from the source data storeâ€ when no other data object with the identifier preexists on the destination data store, the duplicate data object being provided with an additional version number; changing the state of the original data object to â€œlocked to the destination data storeâ€ when the version number of the original data object is unchanged just prior to the changing; modifying the state of the duplicate data object to â€œunlockedâ€ when the additional version number of the duplicate data object is unchanged just prior to the modifying; and deleting the original data object from the source data store.