As i said, Delete job execution will have no impact on database overview.
DB Overview continues to display the aggregated/statistical information until you deactivate the "message overview"
Did you check in your system? Doesn't it display the overview data even after the deletion job?
Activating data collection for the Adapter Engine (Java):
If the property 'messaging.system.statusLog' of the "SAP XI AF Messaging" service (as of 7.10, the name of the server was changed to "XPI Service: Messaging System") does not contain the values 'Send,Recv,Event', add these as follows (do not delete other values that are set):
messaging.system.statusLog=Send,Recv,Event,<other values>
You can then use the property "profile.runtime" of the SAP XI AF Core service to activate data collection for the message overview. To do this, set the value to 'true'.
You must set these properties accordingly in each server node and restart the service.
To deactivate this, set the property "profile.runtime" to the value "false" on each server node. In addition, you must remove the value "Event" from the value list of the property "messaging.system.statusLog". Restart both services "SAP XI AF Messaging" (or "XPI Service: Messaging System" as of Release 7.10) and "SAP XI AF Core" to ensure that the changes take effect.During the deactivation process, all message overview data that was written up to now is deleted, and the message overview is reset to its initial status.