1. To get the maximum
assume Referencing Table(table having foreign key, referencing an attribute in relation S) as R (with 100 tuples)
assume Referenced Table as S(with 9 tuples)
then maximum will be 100 for join on referential integrity constrainst
this will happen when the there is no null values in R for referencing attribute(then every the tuple will be joined with the corresponding matching tuple in the relation S).
hence maximum is 100
2. we get the minimum number of tuples on join when for all the tuples referencing attribute is NULL in
then there will be no tuples on join
hence minimum will be 0
correct me if am wrong.