select * from student;
    update student set sex = ‘人‘ where stuNo = ‘00011‘;
    commit;
    rollback; -- 回滚至上一commit之后 
  show autocommit;  -- 默认off
  set autoCommit on;
  set autoCommit off;
    
    create table AA(
      AA char(10)
    );  -- 隐式commit
  select * from bankcount;  
  -- 多条语句 事务
  update bankcount set money = money - 10000 where countno = ‘110 000 2000 888‘;
  update bankcount set money = money + 10000 where countno = ‘110 000 2000 889‘;
  rollback;
  commit;
  
  -- rollback   定义保存点 savePoint;
  SAVEPOINT aa;
    update bankcount set money = money + 10000 where countno = ‘110 000 2000 888‘;
  SAVEPOINT bb;
    update bankcount set money = money - 10000 where countno = ‘110 000 2000 889‘;
  rollback to bb;   -- 回滚之保存点之后
  commit;