Do the following exercises:

1. Write a PL/SQL procedure that receives two movie IDs and an integer amount and “transfers” a given amount of rank value from a source movie to a destination movie. Note that this doesn’t make much sense in the context of the movie database, but it’s similar to money transfers in a banking database.

   Your procedure should be designed in such a way that it can be run simultaneously by the following sample script to separate threads and still give a consistent result.

   BEGIN
   	FOR i IN 1..10000 LOOP
   		transferRank(176712, 176711, 0.1);
   		COMMIT;
   		transferRank(176711, 176712, 0.1);
   		COMMIT;
   	END LOOP;
   END;

   This script moves rank points between two movies (Kill Bill 1 and Kill Bill 2). Note the following.

   • Your procedure should check the values it receives, raising exceptions as appropriate.
   • Don’t allow the rank value to drop below 0.
   • To make your transaction logic explicit, please use declared exceptions as follows.

     CREATE OR REPLACE PROCEDURE yourProcedure
     	my_exception EXCEPTION;
     BEGIN
     	...some code...
     	RAISE my_exception;
     	...some more code...
     EXCEPTION
     	WHEN my_exception THEN
     		...error handling code for your exception...
     	WHEN my_other_exception THEN
     		...error handling code for my_other_exception(s)...
     END;

   Store your solution in homework10.sql.

2. Complete the programming elements for the lab exercises.

Checking in

We will grade your work according to the following criteria:

• 50% — Exercise 1
• 50% — Exercise 2