The split/join transaction model was proposed for open-ended activities such as computer-aided design and manufacturing (CAD/CAM). Open-ended activities are characterized by uncertain duration, uncertain developments and interaction with other concurrent activities. Due to these characteristics, sometimes it is desirable to release earlier modified data of a transaction to other transactions. The split/join transaction model provides two operations to dynamically restructure transactions, namely split and join. A transaction T may split into two transactions Ta and Tb, providing applications with a mechanism to release data objects that are no longer needed and, hence, release intermediate results to other transactions. Two transactions can also join together to become one transaction, or use combinations of split and join to allow transfer of resources from one transaction to another.