A transaction control unit is the group of targets connected to an active source that generates commits or an effective transaction generator. A transaction control unit is a subset of a target load order group and may contain multiple target connection groups.
When the Integration Service reaches the commit point for all targets in a transaction control unit, it issues commits sequentially for each target.
The following image shows a transaction control unit with a Transaction Control transformation:
Target Connection Group 1
Target Connection Group 2
Target Connection Group 3
Target Connection Group 4
Target Connection Unit 1
Target Connection Unit 2
Target Load Order Group
In this example, T5_ora1 uses the same connection name as T1_ora1 and T2_ora1. Because T5_ora1 is connected to a separate Transaction Control transformation, it is in a separate transaction control unit and target connection group. If you connect T5_ora1 to tc_TransactionControlUnit1, it will be in the same transaction control unit as all targets and in the same target connection group as T1_ora1 and T2_ora1.