Definition
If several data elements belong to the same processing unit, this unit is known as a transaction-oriented data unit or Queue unit.
Each relevant data element must retain a specific sequence ID:
Q_SINGLE (S) |
Individual element |
Q_FIRST (F) |
First element |
Q_MIDDLE () |
Not first/last element |
Q_LAST (L) |
Last element |

A processing program, which is active at a later time, can only delete the data in a queue unit, if the last data object has been acknowledged as processed.