Jump to level 1 session begins SET GLOBAL TRANSACTION ISOLATION LEVEL SERIALIZABLE; session ends session begins SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED; transaction 1 Select each transaction's isolation level. transaction 1 Pick transaction 2 Pick transaction 2 transaction 3 Pick SET SESSION TRANSACTION transaction 4 Pick ISOLATION LEVEL REPEATABLE READ; transaction 3 transaction 5 Pick transaction 4 SET TRANSACTION ISOLATION LEVEL READ COMMITTED; transaction 5 session ends Check Next READ COMMITTED READ UNCOMMITTED REPEATABLE READ SERIALIZABLE