Difference

Cars and drivers that have been victims but not causes for accidents within the same year

Acc_victim - Acc_cause

Acc_victim car driver year
  CEF234 Mike 2000
DFG456 Bill 2000
DFG456 Bill 2001

Acc_cause car driver year
  ABC123 Mary 2001
DFG456 Bill 2001
CEF234 David 2000

 
Final result is ready. In practice this operation is typically carried out by first sorting the rows of both tables and then merging them and without duplicates.

 
RESULT car driver year
  CEF234 Mike 2000
DFG456 Bill 2000

Ready