Postdecision phase
During the postdecision phase, the
coordinator and participants perform the following dialog:
- Coordinator
- The coordinator writes the commit record or rollback record to the coordinator's logical log and then directs each participant database server to either commit or roll back the transaction.
- Participants
- If the coordinator issued a commit message, the participants commit the transaction by writing the commit record to the logical log and then sending a message to the coordinator acknowledging that the transaction was committed. If the coordinator issued a rollback message, the participants roll back the transaction but do not send an acknowledgment to the coordinator.
- Coordinator
- If the coordinator issued a message to commit the transaction, it waits to receive acknowledgment from each participant before it ends the global transaction. If the coordinator issued a message to roll back the transaction, it does not wait for acknowledgments from the participants.