手工恢复控制文件的深入解析(四)
*Plus: Release 11.1.0.6.0 - Production on 星期五 6月 7 23:54:22 2013
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连接到:
Oracle Database 11g Enterprise Edition Release 11.1.0.6.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SYS@orcl#alter session set events 'immediate trace name controlf level 8';
会话已更改。
SYS@orcl#shutdown abort;
ORACLE 例程已经关闭。
SYS@orcl#
这个时候在查看一下这两次转储的控制文件信息：
发现如下是不一样的信息：
第一次转储信息如下：
DUMP OF CONTROL FILES, Seq # 14348 = 0x380c
Control Seq=14348=0x380c, File size=612=0x264
Database checkpoint: Thread=1 scn: 0x0000.004b586f
Controlfile Checkpointed at scn: 0x0000.004b5b11 06/07/2013 23:52:17
THREAD #1 - status:0x2 flags:0x0 dirty:73
low cache rba:(0x3.90df.0) on disk rba:(0x3.9223.0)
on disk scn: 0x0000.004b5b48 06/07/2013 23:53:24
heartbeat: 817528803 mount id: 1345278620
Change tracking state=2, file index=15, checkpoint count=9
Checkpointed at scn: 0x0000.004b586f 06/07/2013 23:38:44
thread:1 rba:(0x3.8e76.10)
Checkpoint cnt:673 scn: 0x0000.004b586f 06/07/2013 23:38:44
Checkpoint cnt:665 scn: 0x0000.004b586f 06/07/2013 23:38:44
Checkpoint cnt:597 scn: 0x0000.004b586f 06/07/2013 23:38:44
Checkpoint cnt:663 scn: 0x0000.004b586f 06/07/2013 23:38:44
第二次转储的信息如下：
DUMP OF CONTROL FILES, Seq # 14352 = 0x3810
Control Seq=14352=0x3810, File size=612=0x264
Database checkpoint: Thread=1 scn: 0x0000.004b5b5e
Controlfile Checkpointed at scn: 0x0000.004b5b62 06/07/2013 23:54:20
THREAD #1 - status:0x2 flags:0x0 dirty:28
low cache rba:(0x3.9229.0) on disk rba:(0x3.923b.0)
on disk scn: 0x0000.004b5b6f 06/07/2013 23:54:24
heartbeat: 817528822 mount id: 1345278620
Change tracking state=2, file index=15, checkpoint count=10
Checkpointed at scn: 0x0000.004b5b5e 06/07/2013 23:54:16
thread:1 rba:(0x3.9226.10)
Checkpoint cnt:674 scn: 0x0000.004b5b5e 06/07/2013 23:54:16
Checkpoint cnt:666 scn: 0x0000.004b5b5e 06/07/2013 23:54:16
Checkpoint cnt:598 scn: 0x0000.004b5b5e 06/07/2013 23:54:16
Checkpoint cnt:664 scn: 0x0000.004b5b5e 06/07/2013 23:54:16
可以看到控制文件序列不一样了，database checkpoint scn不一样了，心跳不一样了，checkpoint at scn不一样了。
然后我们在看一下在启动到mount状态下查看一下数据文件中的控制文件信息和数据文件的头部信息；
SYS@orcl#show parameter control
NAME TYPE VALUE
------------------------------------ ---------------------- ------------------------------
_optimizer_extended_stats_usage_cont integer 240
rol
_optimizer_join_order_control integer 3
control_file_record_keep_time integer 7
control_files string /opt/oracle/oradata/ORCL/contr
olfile/o1_mf_7q9c8orh_.ctl, /o
pt/oracle/flash_recovery_area/
ORCL/controlfile/o1_mf_7q9c8pc
f_.ctl
control_management_pack_access string DIAGNOSTIC+TUNING
SYS@orcl#!
oracle@oracle:~> cd oradata/ORCL/controlfile/
oracle@oracle:~/oradata/ORCL/controlfile> rm o1_mf_7q9c8orh_.ctl
oracle@oracle:~/oradata/ORCL/controlfile> rm /opt/oracle/flash_recovery_area/ORCL/co