set transaction isolation level read committed; set transaction isolation level serializable; rollback; set transaction isolation level serializable; rollback; set transaction read only; rollback; begin set transaction read only; rollback; end; / --exec dbms_transaction.read_only; alter session set isolation_level=serializable; rollback; alter session set isolation_level=read committed; begin execute immediate 'alter session set isolation_level=serializable'; end; / rollback;
ALTER SESSION SET isolation_level 与 SET TRANSACTION ISOLATION LEVEL 区别 1: set transaction readonly只能设置SERIALIZABLE | READ COMMITTED 而ALTER SESSION SET isolation_level 可以设置任何事务