Oracle误删除了日志，我们公司的oracle数据库被人误删除了在线日志online redo

可以尝试使用PRM-DUL恢复无法打开的oracle数据库，也可以尝试如下手法来解决问题：

【Oracle数据恢复】Redo Log重做日志文件坏块Corruption的解决 ORA-16038 ORA-00354 ORA-00353 ORA-00367 ORA-01624

ORA-16038 log %s sequence# %s cannot be archived

ORA-354 corrupt redo log block header

ORA-353 log corruption near block change time

ORA-367 checksum error in log file header

[oracle@mlab2 ~]$ oerr ora 16038

16038, 00000, "log %s sequence# %s cannot be archived"

// *Cause: An attempt was made to archive the named file, but the

// file could not be archived. Examine the secondary error

// messages to determine the cause of the error.

// *Action: No action is required.

[oracle@mlab2 ~]$ oerr ora 354

00354, 00000, "corrupt redo log block header"

// *Cause: The block header on the redo block indicated by the accompanying

// error, is not reasonable.

// *Action: Do recovery with a good version of the log or do time based

// recovery up to the indicated time. If this happens when archiving,

// archiving of the problem log can be skipped by clearing the log

// with the UNARCHIVED option. This must be followed by a backup of

// every datafile to insure recoverability of the database.

[oracle@mlab2 ~]$ oerr ora 353

00353, 00000, "log corruption near block %s change %s time %s"

// *Cause: Some type of redo log corruption has been discovered. This error

// describes the location of the corruption. Accompanying errors

// describe the type of corruption.

// *Action: Do recovery with a good version of the log or do incomplete

// recovery up to the indicated change or time.

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[oracle@mlab2 ~]$ oerr ora 367

00367, 00000, "checksum error in log file header"

// *Cause: The file header for the redo log contains a checksum that does

// not match the value calculated from the file header as read from

// disk. This means the file header is corrupted

// *Action: Find the correct file and try again.

对于不同状态的在线日志文件online redo logfile 损坏/坏块，有不同的解决方案。

对于以下2种情况将不能drop online的redo logfile，他们是：

如果仅仅有2个redo logfile groups

损坏的redo logfile文件属于当前日志组 current logfile groupV$LOG.STATUS=CURRENT

解决方案大致如下：

可以通过clear 命令来清理有问题的日志文件，语法如下：

alter database clear <unarchived>logfile group <integer>

alter database clear <unarchived>logfile ‘<filename>'

例如：

alter database clear logfile group 1

alter database clear unarchived logfile group 1

对于status=current 或者 status=active的日志将无法被清理， 如果清理会报 ORA-01624:

SQL>alter database clear unarchived logfile group 5

alter database clear unarchived logfile group 5

*

ERROR at line 1:

ORA-01624: log 5 needed for crash recovery of instance G10R25 (thread 1)

ORA-00312: online log 5 thread 1: '/s01/G10R25/onlinelog/o1_mf_5_954q1vdo_.log'

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[oracle@vrh8 ~]$ oerr ora 1624

01624, 00000, "log %s needed for crash recovery of instance %s (thread %s)"

// *Cause: A log cannot be dropped or cleared until the thread's checkpoint

// has advanced out of the log.

// *Action: If the database is not open, then open it. Crash recovery will

// advance the checkpoint. If the database is open force a global

// checkpoint. If the log is corrupted so that the database cannot

// be opened, it may be necessary to do incomplete recovery until

// cancel at this log.

对于status=active的日志较为简单，只要能顺利完成一个alter system checkpoint就可以将其状态改为INACTIVE之后再CLEAR。

对于status=current的online redo logfile则比较麻烦，一般需要动用隐藏参数”_ALLOW_RESETLOGS_CORRUPTION”

如果自己搞不定可以找诗檀软件专业ORACLE数据库修复团队成员帮您恢复!

诗檀软件专业数据库修复团队

恢复的前提是备份；

数据库有什么备份，exp还是rman

如果有exp备份：直接imp数据

如果有rman备份：可以基于时间不完全恢复，将数据库恢复到误删除之前的时刻

如果没有备份但是开闪回了，可以闪回数据库或闪回表

oracle数据库恢复,主要包括

(1)系统崩溃只剩下数据文件的情况下的恢复,甚至没有system表空间而只有数据表空间的情况下的恢复.只要提供数据文件就可恢复.

(2)

undo

system

表空间损坏数据恢复

.

(3)

非归档或者归档模式下误

delete

数据的恢复、误删除表空间的恢复、

drop

truncate

表的恢复

.

(4)

数据库中有大量CLOB

BLOB对象数据恢复等情况以及各种ora-错误的修复.

(5)

DMP文件损坏导致文件不能导入数据库的数据恢复

(6)

oracle数据库中数据文件出现坏块情况下的恢复.

(7)

oracle数据库无数据文件但有日志的情况下的恢复.

(8)

UNIX、WINDOWS下ORACLE数据文件被误删除情况下的数据库恢复.

(9)

Oracle10G、Oracle11G

的ASM损坏的数据库恢复.

(10)

Oracle10G、Oracle11G

BIFGILE

TABLESPACE大文件表空间损坏数据恢复

(11)

Oracle9i、Oracle10G、Oracle11G压缩表

压缩表空间损坏数据恢复

(12)Oracle10G

Oracle11G

Expdp导出

Impdp导入DMP文件错误数据恢复

恢复成功率高达90%以上,在数据恢复领域处于国内领先的地位。具体案例见广州拓飞官方网站

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