单表数据文件坏块检查及恢复

一、由于数据库或者操作系统bug、IO错误、内存异常等原因，可能会导致数据库产生坏块，针对是否存在坏块可使用rman进行检查。

二、查找表的file_Id

三、针对存在的file_Id进行检测

RMAN> backup check logical validate datafile 8;

Starting backup at 2022-06-09 14:20:01

using channel ORA_DISK_1

channel ORA_DISK_1: starting full datafile backup set

channel ORA_DISK_1: specifying datafile(s) in backup set

input datafile file number=00008 name=+DGROUP1/calldb/datafile/data_bs03.dbf

channel ORA_DISK_1: backup set complete, elapsed time: 00:00:55

List of Datafiles

=================

File Status Marked Corrupt Empty Blocks Blocks Examined High SCN

---- ------ -------------- ------------ --------------- ----------

8    OK     0              1            2097152         15913565598284

  File Name: +DGROUP1/cadb/datafile/data03.dbf

  Block Type Blocks Failing Blocks Processed

  ---------- -------------- ----------------

  Data       0              1874205         

  Index      0              211121          

  Other      0              11825           

Finished backup at 2022-06-09 14:20:56

四、发现坏块后，首先要获得坏块的所属对象、文件号及块位置。如果是索引、视图等坏块，可以删除重建。 

如果是表可以使用rman恢复

RMAN> backup validate datafile 5; --检测数据文件物理坏块信息

RMAN> run {blockrecover datafile 5 block 1345;} --修复单个坏块

RMAN> run {blockrecover corruption list;} ----修复所有记录在V$DATABASE_BLOCK_CORRUPTION中的逻辑坏块。

RMAN> recover datafile ‘/xxx/xx’; --修复数据文件