1）Oracle数据库版本：11.2.0.4；
2）未开启归档；
3）没有备份：无RMAN备份、无DUMP备份；
4）数据库redo log 日志组，每组只有一个成员；
2、问题出现原因
因公司断电，导致生产数据库宕机，开启后，出现ORA-00600[2662]问题：ORA-00600: internal error code, arguments: [2662], [2], [1424107441], [2], [1424142235], [8388617], [], []。
通过查看数据库状态，只能开启到mount状态，并且有一个日志组文件损坏，而且损坏的是current redo log，并且这个组中，只有这一个日志组成员。
ORA-00600[2662]原因如下：
1）A data block SCN is ahead of the current SCN.(SCN不一致)
2）Bug 14351566 ORA-600 [kclchkblk_4] ORA-600 [2662] when doing flash back；
3、SCN简介
SCN即系统改变号（System Change Number），是在某个时间点定义数据库已提交版本的时间戳标记。 Oracle为每个已提交的事务分配一个唯一的SCN。 SCN的值是对数据库进行更改的逻辑时间点。 Oracle使用此编号记录对数据库所做的更改。在数据库中，SCN也可以说是无处不在，数据文件头，控制文件，数据块头，日志文件等等都标记着SCN。也正是这样，数据库的一致性维护和SCN密切相关。不管是数据的备份，恢复都是离不开SCN的。
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二、问题处理思路
排除了因为Bug导致ORA-00600[2662]的错误，那么错误就定位在SCN不一致上面。
因为没有可用的日志、备份、归档等条件，只能采用重建控制文件，并通过设置Oracle内部隐含参数_allow_resetlogs_corruption=TRUE跳过一致性检查，强制open数据库。
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三、解决步骤
1、参数文件中加入_allow_resetlogs_corruption=TRUE
alter system set _allow_resetlogs_corruption=TRUE scope=spfile;
注意：
即便加上此参数，数据库在此时开启，仍然会爆出ORA-00600[2662]；
如果之前在无法open数据库的时候，加上此参数，仍然会爆出ORA-00600[2662]。
2、重建控制文件
CREATE CONTROLFILE REUSE DATABASE "TRSDB" RESETLOGS NOARCHIVELOG --注意：因为数据库本身就是非归档模式，所以也以非归档模式重建，在追加完SCN后，open数据库，直接open就可。
-- SET STANDBY TO MAXIMIZE PERFORMANCE
MAXLOGFILES 5
MAXLOGMEMBERS 3
MAXDATAFILES 100
MAXINSTANCES 1
MAXLOGHISTORY 226
LOGFILE
GROUP 1 '/home/oracle/app/oracle/oradata/trsdb/redo01.log' SIZE 50M, ---等数据库恢复后，需要在日志组中在加上一个日志组成员（一个日志组至少两个成员）
GROUP 2 '/home/oracle/app/oracle/oradata/trsdb/redo02.log' SIZE 50M,
GROUP 3 '/home/oracle/app/oracle/oradata/trsdb/redo03.log' SIZE 50M
-- STANDBY LOGFILE
DATAFILE
'/home/oracle/app/oracle/oradata/trsdb/system01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sysaux01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb12_2.dbf',
'/home/oracle/app/oracle/oradata/trsdb/users01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/bigdb.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb02.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb03.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb04.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb05.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb06.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb07.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb08.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb09.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb10.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb11.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb12.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device02.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device03.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device04.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device05.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device06.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device07.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device08.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device09.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device10.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device11.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device12.dbf',
'/home/oracle/app/oracle/oradata/trsdb/bigdb-01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb08-01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb09-01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb10-1.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb07-01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb06-01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb05-01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device11_2.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device11_3.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device11_4.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device11_5.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb12_1.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb01a.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb01b.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb021.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb02-01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb07-02.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb10-02.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb03-02.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb06-02.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb11-02.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb09-02.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb04-03.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb05-02.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb02-02.dbf',
'/home/oracle/app/oracle/oradata/trsdb/bigdb-02.dbf',
'/home/oracle/app/oracle/oradata/trsdb/bigdb-03.dbf',
'/home/oracle/app/oracle/oradata/trsdb/bigdb-04.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb01c.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb03-01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb04-02.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/SGDB07_2018060817_1.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/SGDB08_2018061109_2.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/SGDB09_2018061917_1.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/SGDB10_2018062618_3.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/SGDB12_2018071420_1.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/SGDB02_2018072309_1.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/SGDB01_2018072409_1.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/SGDB01_2018072409_2.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/DEVICE01_2018072409_1.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/DEVICE02_2018072409_1.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/DEVICE03_2018072717_1.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/SGDB06_2018072717_1.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/DEVICE08_2018072717_2.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/DEVICE09_2018072717_2.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/SGDB05_2018072717_2.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/SGDB03_2018072718_1.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/DEVICE06_2018072718_2.dbf',
'/home/oracle/app/oracle/product/11.2.0/dbhome_1/dbs/DEVICE07_2018072718_2.dbf',
'/home/oracle/app/oracle/oradata/trsdb/device04-01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb04-01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb09-03.dbf',
'/home/oracle/app/oracle/oradata/trsdb/sgdb08-02.dbf',
'/home/oracle/app/oracle/oradata/trsdb/audit01.dbf',
'/home/oracle/app/oracle/oradata/trsdb/undotbs02.dbf'
;
3、使用oradebug poke推进SCN
1）oradebug setmypid
2）oradebug dumpvar sga kcsgscn_
3）oradebug poke 0x060012658 8 10014077592
4）oradebug dumpvar sga kcsgscn_
5）alter database open;
至此数据库恢复完毕，后面还需要将数据导出，并重建这个非常规恢复的数据库。