You are working on a very large database. You had performed a binary backup of the control file a month ago. After this you added a few tablespaces， and dropped a couple of tablespaces. This morning， due to hardware failure， you lost all your control files. How would you recover the database from this situation？（） A。 B。 C。 D。 E。
成角透视
轴上零件作周向固定的目的：是为了保证（）转矩时，轴上零件与轴之间不产生（）。
防污染类
Click the Exhibit button. What is the result？（） The code will deadlock.。 The code may run with output "2 0 6 4".。 The code may run with no output.。 The code may run with output "0 6".。 An exception is thrown at runtime.。 The code may run with output "0 2 4 6".。
采用一台三相三柱式电压互感器，接成Y----Y形接线，该方式能进行（）
