JDBC 事务

1.开始事务

X.SetAutoCommit(false) 关闭自动提交，相当于开始事务

2 .回滚
X.rollback() 撤销全部操作


3 .定点回滚

Savepoint A =X.setSavepoint();

X.rollback(A) 回滚到A点

4.提交
X.commit();