活动第11/12次（2018-04-14星期六上下午）

botang

select  * from v$sgastat;

select  d.CHECKPOINT_CHANGE#  from v_$database d;

select  * from v$datafile;


1960000  doing   Incremental  not done    1952278-1959998(RBA->)   1959999


1970000 doing   Incremental   not done   19599999- Commplete Checkpoint -1969998(RBA->)  1969999

日常看见的都是增量检查点：只有两种增量检查点：
一种是日志切换：

1. Mon Apr 16 11:19:41 2018
   
2. Completed checkpoint up to RBA [0x74.2.10], SCN: 1960197
   
3. Mon Apr 16 11:32:48 2018
   
4. Thread 1 cannot allocate new log, sequence 117
   
5. Private strand flush not complete
   
6.   Current log# 2 seq# 116 mem# 0: +DATA/orcl/onlinelog/group_2.262.816169639
   
7.   Current log# 2 seq# 116 mem# 1: +FRA/orcl/onlinelog/group_2.258.816169639
   
8. Beginning log switch checkpoint up to RBA [0x75.2.10], SCN: 1961318
   
9. Thread 1 advanced to log sequence 117 (LGWR switch)
   
10.   Current log# 3 seq# 117 mem# 0: +DATA/orcl/onlinelog/group_3.263.816169641
    
11.   Current log# 3 seq# 117 mem# 1: +FRA/orcl/onlinelog/group_3.259.816169641
    
12. Mon Apr 16 11:32:48 2018
    
13. Archived Log entry 130 added for thread 1 sequence 116 ID 0x596b1d0e dest 1:
    
14. Mon Apr 16 11:35:48 2018
    

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另一种是fast_start_mttr_target（前滚的成本是由RBA之后日志的长度和强度决定的）：

1. Incremental checkpoint up to RBA [0x74.b37.0], current log tail at RBA [0x75.240.0]
   
2. Mon Apr 16 11:37:57 2018
   
3. Completed checkpoint up to RBA [0x75.2.10], SCN: 1961318
   

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请在只读数据库中，再查询以遍：

1. select  d.CHECKPOINT_CHANGE#, current_scn  from v_$database d;
   
2. 
   
3. select  d.CHECKPOINT_CHANGE#  from v_$datafile d;
   
4. 
   
5. alter system switch logfile;
   
6. 
   
7. select  * from v$log;
   
8. 
   
9. alter system checkpoint;
   
10. 
    
11. select  * from dba_data_files;
    

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1. alter tablespace users offline ;
   
2. 
   
3. select  * from dba_data_files;
   
4. 
   
5. alter database datafile '+DATA/orcl/datafile/users.259.816169553' offline;
   
6. 
   
7. alter database datafile '+DATA/orcl/datafile/users.259.816169553' online;
   
8. 
   
9. 
   
10. select  d.NAME , d.CHECKPOINT_CHANGE#  from v_$datafile d;
    
11. 
    
12. alter system checkpoint;
    
13. 
    
14. alter tablespace users begin backup;
    
15. 
    
16. select  * from v$backup;
    
17. 
    
18. alter tablespace users end backup;
    

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1. alter system checkpoint;
   
2. 
   
3. select  d.NAME , d.CHECKPOINT_CHANGE#  from v_$datafile d;
   
4. 
   
5. alter tablespace users offline ;
   
6. 
   
7. alter tablespace users online ;
   
8. 
   
9. alter system checkpoint;
   
10. 
    
11. select  d.NAME , d.CHECKPOINT_CHANGE#  from v_$datafile d;
    
12. 
    
13. alter tablespace users read only ;
    
14. 
    
15. alter tablespace users read write ;
    
16. 
    
17. -----
    
18. alter database datafile '+DATA/orcl/datafile/users.259.816169553' offline;
    
19. 
    
20. alter database datafile '+DATA/orcl/datafile/users.259.816169553' online;
    
21. 
    
22. alter tablespace sysaux online;

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1. select  * from v$log;
   
2. 
   
3. alter database add logfile group 4 size  52428800;
   
4. 
   
5. select  * from v$logfile;
   
6. 
   
7. alter database drop logfile group 4;
   
8. 
   
9. alter database add logfile member '/u01/app/oracle/oradata/orcl/redo02c.log' to group 2;
   
10. 
    
11. ------------------------
    
12. 
    
13. alter database drop logfile member '/u01/app/oracle/oradata/orcl/redo02c.log';
    
14. 
    
15. alter system switch logfile;

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1. [oracle@station90 ~]$ . oraenv
   
2. ORACLE_SID = [orcl] ? +ASM
   
3. The Oracle base for ORACLE_HOME=/u01/app/oracle/product/11.2.0/grid is /u01/app/oracle
   
4. [oracle@station90 ~]$ asmcmd  cp +FRA/orcl/controlfile/current.256.816169633  /u01/app/oracle/oradata/orcl/control03.ctl
   
5. copying +FRA/orcl/controlfile/current.256.816169633 -> /u01/app/oracle/oradata/orcl/control03.ctl
   

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