question: Which document has the most draft copies? List its document id and number of draft copies.
#1 return documents 
#2 return draft  copies  of #1 
#3 return number of  #2 for each #1 
#4 return the  highest of #3 
#5 return #1 where #3 is equal to #4 
#6 return document  id of #5 
#7 return #6 ,  #4