Sorry, my English is not that good.
I need a simple IT device tracking sytem at work. For each device I need to know its current location, status and ownership (employee to which it is assigned). Some devices (for example network printers) are not assigned to anyone.
It’s important to keep track of events that cause changes in device’s status, it’s assignment or location.
For example, an event could be "device receipt". This event cause the device status to change from ordered to received. It’s location is set to “storage room”. It's not assigned to anyone. In the schema below, the black relationships keep track of the current situation, while the red part keep also all events time sequence. When an event is registered, the DE, DL and DS relationships must be updated to current values.
My question is: Is it a good design? It does not ensure that the status registered with the event (for example) is the same that is associated to the current device status.
Is it due to ER limitation or a bad design?