Problem #1: Write a view for one of your tables using names different from the names on the table and show the results. Now do a modification to the view itself.
Problem #2: Now do a modification of the data in the table using the view.
Problem #3: Do a view with a check constraint.
Problem #4: Create a sequence with a very limited range and a table. Use the sequence as you put data into the table.
Problem #5: Insert enough records to hit the max and then alter the sequence.
Problem #6: Create a script to enter a record into a table.