Specifying Task Flow Transaction Start Options
Transaction start options on the called task flow definition specify whether a called ADF bounded task flow should:
Join an existing transaction (requires-existing-transaction)
Create a new transaction (new-transaction)
Create a new one only if there is no existing transaction (requires-transaction)
If no transaction option is specified, a transaction is not started on entry of the called ADF bounded task flow. A run-time exception is thrown if the ADF bounded task flow attempts to access transactional services.