For part 1 * " Make a second copy of your database DB2.sqlite." Means just make a copy and call it DB2.sqlite * In PRAGMA journal_mode=delete; The journal file contains undo logs For part 2 * The code should not be changed when testing the two different isolation levels. Only the part of the code to change the isolation levels should change. * A deadlock is expected to happen in the code when in serializable mode.