OCP-1Z0-052-V8.02-123题

123. You used the IMMEDIATE option to shut down your database instance. Consider the steps that may

occur when a database instance is started and database is opened:

1: SGA is allocated.

2: Control file is read.

3: Redo log files are opened.

4: Instance recovery is started.

5: Background processes are started.

6: Data file headers are checked for consistency.

7: Server parameter file or the initialization parameter file is read.

Which option has the correct order in which these steps occur?

A.7, 1, 5, 2, 3, 6, 4

B.1, 5, 7, 2, 3, 6; step 4 is not required

C.7, 1, 5, 2, 3, 6; step 4 is not required

D.1, 2, 3, 5, 6, 4; step 7 is not required

Answer: C  

答案解析：

参考：http://blog.csdn.net/rlhua/article/details/12237245

参考：7题：http://blog.csdn.net/rlhua/article/details/12250357

 

 

shutdown abort后，再startup，需要用到smon进行实例恢复。

在nomount阶段，读取初始化参数，分配SGA，后台进程启动

在mount阶段，读取控制文件和联机日志文件，查看需要打开哪些数据文件

在open阶段，根据控制文件内容找到数据文件，并打开，因为是IMMEDIATE 关闭的数据库，即是一致性关闭，所以再次启动后，不需要恢复。