RMAN深入解析之--BlockRecover恢复坏块 案例环境： 操作系统：RedHat EL5 Oracle： Oracle 11gR2 案例描述： 通过块介质恢复（Block Media Recover:BMR)执行块级别的恢复操作来修复Oracle数据库上的逻辑或物理上损坏的数据块。 1、模拟数据块被破坏 10:26:48
RMAN深入解析之--BlockRecover恢复坏块
案例环境：
操作系统：RedHat EL5
Oracle： Oracle 11gR2
案例描述：
通过块介质恢复（Block Media Recover:BMR)执行块级别的恢复操作来修复Oracle数据库上的逻辑或物理上损坏的数据块。
1、模拟数据块被破坏
10:26:48 SYS@ prod>conn scott/tiger Connected. 10:26:51 SCOTT@ prod>select * from tab; TNAME TABTYPE CLUSTERID ------------------------------ ------- ---------- BONUS TABLE DEPT TABLE EMP TABLE EMP1 TABLE SALGRADE TABLE Elapsed: 00:00:00.10 10:26:55 SCOTT@ prod> 10:27:37 SYS@ prod>desc dba_segments Name Null? Type ----------------------------------------------------------------- -------- ------------- OWNER VARCHAR2(30) SEGMENT_NAME VARCHAR2(81) PARTITION_NAME VARCHAR2(30) SEGMENT_TYPE VARCHAR2(18) SEGMENT_SUBTYPE VARCHAR2(10) TABLESPACE_NAME VARCHAR2(30) HEADER_FILE NUMBER HEADER_BLOCK NUMBER BYTES NUMBER BLOCKS NUMBER EXTENTS NUMBER INITIAL_EXTENT NUMBER NEXT_EXTENT NUMBER MIN_EXTENTS NUMBER MAX_EXTENTS NUMBER MAX_SIZE NUMBER RETENTION VARCHAR2(7) MINRETENTION NUMBER PCT_INCREASE NUMBER FREELISTS NUMBER FREELIST_GROUPS NUMBER RELATIVE_FNO NUMBER BUFFER_POOL VARCHAR2(7) FLASH_CACHE VARCHAR2(7) CELL_FLASH_CACHE VARCHAR2(7) 10:27:41 SYS@ prod>col segment_name for a20 10:27:59 SYS@ prod>select owner,segment_name,SEGMENT_TYPE,HEADER_BLOCK from dba_segments 10:29:06 2 where owner='SCOTT' and segment_name='EMP1'; OWNER SEGMENT_NAME SEGMENT_TYPE HEADER_BLOCK ------------------------------ -------------------- ------------------ ------------ SCOTT EMP1 TABLE 170
通过以上查询，可以知道EMP1 table的segment header block为170；利用Uedit32，打开数据文件（users01.dbf)进行编辑破坏！
以下是计算block 170和block 171在Uedit32编辑中的offset：
10:29:24 SYS@ prod>select to_char(170*8*1024, 'xxxxxxxxxxxxxxxxxxxxx') from dual;
TO_CHAR(170*8*1024,'XX
----------------------
154000
10:30:27 SYS@ prod>select to_char(171*8*1024, 'xxxxxxxxxxxxxxxxxxxxx') from dual;
TO_CHAR(171*8*1024,'XX
----------------------
156000
以下是Uedit32编辑users01.dbf图片：
通过转储数据块验证：
10:30:37 SYS@ prod>alter system dump datafile 4 block 170;
System altered.
[oracle@rh6 ~]$ ls -lt /u01/app/oracle/diag/rdbms/prod/prod/trace/|more
total 14300
-rw-r----- 1 oracle oinstall 4492 Jul 15 11:34 prod_ora_2883.trc -rw-r----- 1 oracle oinstall 69 Jul 15 11:34 prod_ora_2883.trm -rw-r----- 1 oracle oinstall 557756 Jul 15 10:17 alert_prod.log -rw-r----- 1 oracle oinstall 947 Jul 15 10:17 prod_ckpt_2541.trc -rw-r----- 1 oracle oinstall 59 Jul 15 10:17 prod_ckpt_2541.trm -rw-r----- 1 oracle oinstall 1783 Jul 15 10:12 prod_j000_2588.trc -rw-r----- 1 oracle oinstall 80 Jul 15 10:12 prod_j000_2588.trm
查看转储文件：
[oracle@rh6 ~]$ cat /u01/app/oracle/diag/rdbms/prod/prod/trace/prod_ora_2883.trc|more
Trace file /u01/app/oracle/diag/rdbms/prod/prod/trace/prod_ora_2883.trc Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options ORACLE_HOME = /u01/app/oracle/product/11.2.0/db_1 System name: Linux Node name: rh6 Release: 2.6.32-358.el6.x86_64 Version: #1 SMP Tue Jan 29 11:47:41 EST 2013 Machine: x86_64 Instance name: prod Redo thread mounted by this instance: 1 Oracle process number: 26 Unix process pid: 2883, image: oracle@rh6 (TNS V1-V3) *** 2014-07-15 11:34:50.092 *** SESSION ID:(37.32) 2014-07-15 11:34:50.092 *** CLIENT ID:() 2014-07-15 11:34:50.092 *** SERVICE NAME:(SYS$USERS) 2014-07-15 11:34:50.092 *** MODULE NAME:(sqlplus@rh6 (TNS V1-V3)) 2014-07-15 11:34:50.092 *** ACTION NAME:() 2014-07-15 11:34:50.092 Start dump data blocks tsn: 4 file#:4 minblk 170 maxblk 170 Block dump from cache: Dump of buffer cache at level 4 for tsn=4, rdba=16777386 Block dump from disk: buffer tsn: 4 rdba: 0x010000aa (4/170) scn: 0x0000.001f891c seq: 0x02 flg: 0x04 tail: 0x891c2302 frmt: 0x02 chkval: 0x8eee type: 0x23=PAGETABLE SEGMENT HEADER Hex dump of block: st=0, typ_found=1 Dump of memory from 0x00007F7DFC5C7A00 to 0x00007F7DFC5C9A00
7F7DFC5C7A00 0000A223 010000AA 001F891C 04020000 [#...............]
---此行内容与Uedit32打开内容一致
7F7DFC5C7A10 00008EEE 00000000 00000000 00000000 [................]
7F7DFC5C7A20 00000000 00000001 00000008 00000A9C [................]
7F7DFC5C7A30 00000000 00000008 00000008 010000B0 [................]
7F7DFC5C7A40 00000000 00000000 00000000 00000008 [................]
7F7DFC5C7A50 00000000 00000000 00000000 00000000 [................]
7F7DFC5C7A60 00000008 00000008 010000B0 00000000 [................]
7F7DFC5C7A70 00000000 00000000 00000008 010000A8 [................]
7F7DFC5C7A80 010000A8 00000000 00000000 00000000 [................]
7F7DFC5C7A90 00000000 00000000 00000000 00000000 [................]
Repeat 3 times
7F7DFC5C7AD0 00000001 00002000 00000000 00001434 [..... ......4...]
7F7DFC5C7AE0 00000000 010000A9 00000001 010000A8 [................]
7F7DFC5C7AF0 010000A9 00000000 00000000 00000000 [................]
7F7DFC5C7B00 00000000 00000000 00000001 00000000 [................]
7F7DFC5C7B10 0001257B 10000000 010000A8 00000008 [{%..............]
7F7DFC5C7B20 00000000 00000000 00000000 00000000 [................]
Repeat 152 times
7F7DFC5C84B0 010000A8 010000AB 00000000 00000000 [................]
7F7DFC5C84C0 00000000 00000000 00000000 00000000 [................]
Repeat 151 times
7F7DFC5C8E40 00000000 00000000 010000A9 00000000 [................]
7F7DFC5C8E50 00000000 00000000 00000000 00000000 [................]
Repeat 185 times
7F7DFC5C99F0 00000000 00000000 00000000 891C2302 [.............#..]
Extent Control Header
-----------------------------------------------------------------
Extent Header:: spare1: 0 spare2: 0 #extents: 1 #blocks: 8
last map 0x00000000 #maps: 0 offset: 2716
Highwater:: 0x010000b0 ext#: 0 blk#: 8 ext size: 8
#blocks in seg. hdr's freelists: 0
#blocks below: 8
mapblk 0x00000000 offset: 0
Unlocked
--------------------------------------------------------
Low HighWater Mark :
Highwater:: 0x010000b0 ext#: 0 blk#: 8 ext size: 8
#blocks in seg. hdr's freelists: 0
#blocks below: 8
mapblk 0x00000000 offset: 0
Level 1 BMB for High HWM block: 0x010000a8
Level 1 BMB for Low HWM block: 0x010000a8
--------------------------------------------------------
Segment Type: 1 nl2: 1 blksz: 8192 fbsz: 0
L2 Array start offset: 0x00001434
First Level 3 BMB: 0x00000000
L2 Hint for inserts: 0x010000a9
Last Level 1 BMB: 0x010000a8
Last Level II BMB: 0x010000a9
Last Level III BMB: 0x00000000
Map Header:: next 0x00000000 #extents: 1 obj#: 75131 flag: 0x10000000
Inc # 0
Extent Map
-----------------------------------------------------------------
0x010000a8 length: 8
Auxillary Map
--------------------------------------------------------
Extent 0 : L1 dba: 0x010000a8 Data dba: 0x010000ab
--------------------------------------------------------
Second Level Bitmap block DBAs
--------------------------------------------------------
DBA 1: 0x010000a9
End dump data blocks tsn: 4 file#: 4 minblk 170 maxblk 1702、将Uedit32（通过16进制编辑功能）编辑过的数据文件上传到数据库
13:59:58 SYS@ prod>alter system flush buffer_cache;
System altered.
读取数据出错：
14:00:05 SYS@ prod>select * from scott.emp1; select * from scott.emp1 * ERROR at line 1: ORA-01578: ORACLE data block corrupted (file # 4, block # 170) ORA-01110: data file 4: '/u01/app/oracle/oradata/prod/users01.dbf'
验证数据文件：
[oracle@rh6 ~]$ dbv file=/u01/app/oracle/oradata/prod/users01.dbf blocksize=8192
DBVERIFY: Release 11.2.0.1.0 - Production on Tue Jul 15 13:59:41 2014 Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved. DBVERIFY - Verification starting : FILE = /u01/app/oracle/oradata/prod/users01.dbf Page 170 is marked corrupt Corrupt block relative dba: 0x010000aa (file 4, block 170) Bad check value found during dbv: Data in bad block: type: 35 format: 2 rdba: 0x010000aa last change scn: 0x0000.001f891c seq: 0x2 flg: 0x04 spare1: 0x0 spare2: 0x0 spare3: 0x0 consistency value in tail: 0x891c2302 check value in block header: 0x8eee computed block checksum: 0x2020 Page 171 is marked corrupt Corrupt block relative dba: 0x010000ab (file 4, block 171) Bad header found during dbv: Data in bad block: type: 6 format: 2 rdba: 0x012020ab last change scn: 0x2020.201f890b seq: 0x2 flg: 0x04 spare1: 0x20 spare2: 0x20 spare3: 0x2020 consistency value in tail: 0x890b0602 check value in block header: 0xcf8b computed block checksum: 0x2e00 Page 172 is marked corrupt Corrupt block relative dba: 0x010000ac (file 4, block 172) Bad header found during dbv: Data in bad block: type: 6 format: 2 rdba: 0x012020ac last change scn: 0x2020.201f891c seq: 0x3 flg: 0x06 spare1: 0x20 spare2: 0x20 spare3: 0x2020 consistency value in tail: 0x891c0603 check value in block header: 0xa5b1 computed block checksum: 0x0 Page 173 is marked corrupt Corrupt block relative dba: 0x010000ad (file 4, block 173) Bad header found during dbv: Data in bad block: type: 6 format: 2 rdba: 0x012020ad last change scn: 0x2020.201f891c seq: 0x1 flg: 0x04 spare1: 0x20 spare2: 0x20 spare3: 0x2020 consistency value in tail: 0x891c0601 check value in block header: 0xf6ab computed block checksum: 0x2020 Page 174 is marked corrupt Corrupt block relative dba: 0x010000ae (file 4, block 174) Bad header found during dbv: Data in bad block: type: 6 format: 2 rdba: 0x012020ae last change scn: 0x2020.201f891c seq: 0x1 flg: 0x04 spare1: 0x20 spare2: 0x20 spare3: 0x2020 consistency value in tail: 0x891c0601 check value in block header: 0xcef0 computed block checksum: 0x20 Page 175 is marked corrupt Corrupt block relative dba: 0x010000af (file 4, block 175) Bad header found during dbv: Data in bad block: type: 6 format: 2 rdba: 0x012020af last change scn: 0x2020.201f891c seq: 0x1 flg: 0x04 spare1: 0x20 spare2: 0x20 spare3: 0x2020 consistency value in tail: 0x891c0601 check value in block header: 0x146a computed block checksum: 0x0 Page 176 is marked corrupt Corrupt block relative dba: 0x010000b0 (file 4, block 176) Bad header found during dbv: Data in bad block: type: 6 format: 2 rdba: 0x012020b0 last change scn: 0x2020.201e6219 seq: 0x1 flg: 0x04 spare1: 0x20 spare2: 0x20 spare3: 0x2020 consistency value in tail: 0x62190601 check value in block header: 0x2185 computed block checksum: 0x2020
DBVERIFY - Verification complete
Total Pages Examined : 12800
Total Pages Processed (Data) : 757
Total Pages Failing (Data) : 0
Total Pages Processed (Index): 2
Total Pages Failing (Index): 0
Total Pages Processed (Other): 12024
Total Pages Processed (Seg) : 0
Total Pages Failing (Seg) : 0
Total Pages Empty : 10
Total Pages Marked Corrupt : 7
Total Pages Influx : 0
Total Pages Encrypted : 0
Highest block SCN : 2066716 (0.2066716)
从以上验证结果看：总共有7个数据块（170-176）被破坏！
3、利用RMAN进行修复
[oracle@rh6 ~]$ rman target /
Recovery Manager: Release 11.2.0.1.0 - Production on Tue Jul 15 14:02:16 2014
Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved.
connected to target database: PROD (DBID=239333010)
RMAN> list backup of database;
using target database control file instead of recovery catalog
List of Backup Sets
===================
BS Key Type LV Size Device Type Elapsed Time Completion Time
------- ---- -- ---------- ----------- ------------ ---------------
17 Full 1.13G DISK 00:01:21 03-JUL-14
BP Key: 17 Status: AVAILABLE Compressed: NO Tag: TAG20140703T171545
Piece Name: /u01/app/oracle/product/11.2.0/db_1/dbs/0lpcfu61_1_1
List of Datafiles in backup set 17
File LV Type Ckp SCN Ckp Time Name
---- -- ---- ---------- --------- ----
1 Full 2066885 03-JUL-14 /u01/app/oracle/oradata/prod/system01.dbf
2 Full 2066885 03-JUL-14 /u01/app/oracle/oradata/prod/sysaux01.dbf
3 Full 2066885 03-JUL-14 /u01/app/oracle/oradata/prod/undotbs1.dbf
4 Full 2066885 03-JUL-14 /u01/app/oracle/oradata/prod/users01.dbf
5 Full 2066885 03-JUL-14 /u01/app/oracle/oradata/prod/example01.dbf
6 Full 2066885 03-JUL-14 /u01/app/oracle/oradata/prod/tbs1.dbf
7 Full 2066885 03-JUL-14 /u01/app/oracle/oradata/prod/undotbs2.dbf
8 Full 2066885 03-JUL-14 /u01/app/oracle/oradata/prod/perftbs01.dbfRMAN> blockrecover datafile 4 block 170,171,172,173,174,175,176;
Starting recover at 15-JUL-14 using channel ORA_DISK_1 channel ORA_DISK_1: restoring block(s) channel ORA_DISK_1: specifying block(s) to restore from backup set restoring blocks of datafile 00004 channel ORA_DISK_1: reading from backup piece /u01/app/oracle/product/11.2.0/db_1/dbs/0lpcfu61_1_1 channel ORA_DISK_1: piece handle=/u01/app/oracle/product/11.2.0/db_1/dbs/0lpcfu61_1_1 tag=TAG20140703T171545 channel ORA_DISK_1: restored block(s) from backup piece 1 channel ORA_DISK_1: block restore complete, elapsed time: 00:00:01 starting media recovery media recovery complete, elapsed time: 00:00:07 Finished recover at 15-JUL-14
恢复完成，验证：
RMAN> backup validate database;
Starting backup at 15-JUL-14 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=00001 name=/u01/app/oracle/oradata/prod/system01.dbf input datafile file number=00002 name=/u01/app/oracle/oradata/prod/sysaux01.dbf input datafile file number=00008 name=/u01/app/oracle/oradata/prod/perftbs01.dbf input datafile file number=00004 name=/u01/app/oracle/oradata/prod/users01.dbf input datafile file number=00005 name=/u01/app/oracle/oradata/prod/example01.dbf input datafile file number=00007 name=/u01/app/oracle/oradata/prod/undotbs2.dbf input datafile file number=00006 name=/u01/app/oracle/oradata/prod/tbs1.dbf input datafile file number=00003 name=/u01/app/oracle/oradata/prod/undotbs1.dbf channel ORA_DISK_1: backup set complete, elapsed time: 00:00:45 List of Datafiles ================= File Status Marked Corrupt Empty Blocks Blocks Examined High SCN ---- ------ -------------- ------------ --------------- ---------- 1 OK 0 13407 99852 2117516 File Name: /u01/app/oracle/oradata/prod/system01.dbf Block Type Blocks Failing Blocks Processed ---------- -------------- ---------------- Data 0 67302 Index 0 15344 Other 0 3787 File Status Marked Corrupt Empty Blocks Blocks Examined High SCN ---- ------ -------------- ------------ --------------- ---------- 2 OK 0 17342 66627 2117514 File Name: /u01/app/oracle/oradata/prod/sysaux01.dbf Block Type Blocks Failing Blocks Processed ---------- -------------- ---------------- Data 0 11719 Index 0 7882 Other 0 29617 File Status Marked Corrupt Empty Blocks Blocks Examined High SCN ---- ------ -------------- ------------ --------------- ---------- 3 OK 0 1 128 2056342 File Name: /u01/app/oracle/oradata/prod/undotbs1.dbf Block Type Blocks Failing Blocks Processed ---------- -------------- ---------------- Data 0 0 Index 0 0 Other 0 127 File Status Marked Corrupt Empty Blocks Blocks Examined High SCN ---- ------ -------------- ------------ --------------- ---------- 4 OK 0 11873 12800 2066716 File Name: /u01/app/oracle/oradata/prod/users01.dbf Block Type Blocks Failing Blocks Processed ---------- -------------- ---------------- Data 0 763 Index 0 2 Other 0 162 File Status Marked Corrupt Empty Blocks Blocks Examined High SCN ---- ------ -------------- ------------ --------------- ---------- 5 OK 0 1680 12804 1715036 File Name: /u01/app/oracle/oradata/prod/example01.dbf Block Type Blocks Failing Blocks Processed ---------- -------------- ---------------- Data 0 3987 Index 0 1132 Other 0 6001 File Status Marked Corrupt Empty Blocks Blocks Examined High SCN ---- ------ -------------- ------------ --------------- ---------- 6 OK 0 2 1281 2051631 File Name: /u01/app/oracle/oradata/prod/tbs1.dbf Block Type Blocks Failing Blocks Processed ---------- -------------- ---------------- Data 0 1 Index 0 0 Other 0 1277 File Status Marked Corrupt Empty Blocks Blocks Examined High SCN ---- ------ -------------- ------------ --------------- ---------- 7 OK 0 8833 12800 2117516 File Name: /u01/app/oracle/oradata/prod/undotbs2.dbf Block Type Blocks Failing Blocks Processed ---------- -------------- ---------------- Data 0 0 Index 0 0 Other 0 3967 File Status Marked Corrupt Empty Blocks Blocks Examined High SCN ---- ------ -------------- ------------ --------------- ---------- 8 OK 0 23967 25600 2006072 File Name: /u01/app/oracle/oradata/prod/perftbs01.dbf Block Type Blocks Failing Blocks Processed ---------- -------------- ---------------- Data 0 867 Index 0 261 Other 0 505 channel ORA_DISK_1: starting full datafile backup set channel ORA_DISK_1: specifying datafile(s) in backup set including current control file in backup set including current SPFILE in backup set channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01 List of Control File and SPFILE =============================== File Type Status Blocks Failing Blocks Examined ------------ ------ -------------- --------------- SPFILE OK 0 2 Control File OK 0 594 Finished backup at 15-JUL-14
[oracle@rh6 ~]$ sqlplus '/as sysdba'
SQL*Plus: Release 11.2.0.1.0 Production on Tue Jul 15 14:16:27 2014
Copyright (c) 1982, 2009, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
14:16:27 SYS@ prod>select count(*) from scott.emp1;
COUNT(*)
----------
28
Elapsed: 00:00:00.02
14:16:35 SYS@ prod>select * from scott.emp1;
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
---------- ---------- --------- ---------- --------- ---------- ---------- ----------
7369 SMITH CLERK 7902 17-DEC-80 800 20
7499 ALLEN SALESMAN 7698 20-FEB-81 1600 300 30
7521 WARD SALESMAN 7698 22-FEB-81 1250 500 30
7566 JONES MANAGER 7839 02-APR-81 2975 20
7654 MARTIN SALESMAN 7698 28-SEP-81 1250 1400 30
7698 BLAKE MANAGER 7839 01-MAY-81 2850 30
7782 CLARK MANAGER 7839 09-JUN-81 2450 10
7788 SCOTT ANALYST 7566 19-APR-87 3000 20
7839 KING PRESIDENT 17-NOV-81 5000 10
7844 TURNER SALESMAN 7698 08-SEP-81 1500 0 30
7876 ADAMS CLERK 7788 23-MAY-87 1100 20
7900 JAMES CLERK 7698 03-DEC-81 950 30
7902 FORD ANALYST 7566 03-DEC-81 3000 20
7934 MILLER CLERK 7782 23-JAN-82 1300 10
7369 SMITH CLERK 7902 17-DEC-80 800 20
7499 ALLEN SALESMAN 7698 20-FEB-81 1600 300 30
7521 WARD SALESMAN 7698 22-FEB-81 1250 500 30
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
---------- ---------- --------- ---------- --------- ---------- ---------- ----------
7566 JONES MANAGER 7839 02-APR-81 2975 20
7654 MARTIN SALESMAN 7698 28-SEP-81 1250 1400 30
7698 BLAKE MANAGER 7839 01-MAY-81 2850 30
7782 CLARK MANAGER 7839 09-JUN-81 2450 10
7788 SCOTT ANALYST 7566 19-APR-87 3000 20
7839 KING PRESIDENT 17-NOV-81 5000 10
7844 TURNER SALESMAN 7698 08-SEP-81 1500 0 30
7876 ADAMS CLERK 7788 23-MAY-87 1100 20
7900 JAMES CLERK 7698 03-DEC-81 950 30
7902 FORD ANALYST 7566 03-DEC-81 3000 20
7934 MILLER CLERK 7782 23-JAN-82 1300 10
28 rows selected.
Elapsed: 00:00:00.07读取数据成功！
[oracle@rh6 ~]$ dbv file=/u01/app/oracle/oradata/prod/users01.dbf blocksize=8192
DBVERIFY: Release 11.2.0.1.0 - Production on Tue Jul 15 14:17:22 2014 Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved. DBVERIFY - Verification starting : FILE = /u01/app/oracle/oradata/prod/users01.dbf DBVERIFY - Verification complete Total Pages Examined : 12800 Total Pages Processed (Data) : 763 Total Pages Failing (Data) : 0 Total Pages Processed (Index): 2 Total Pages Failing (Index): 0 Total Pages Processed (Other): 12025 Total Pages Processed (Seg) : 0 Total Pages Failing (Seg) : 0 Total Pages Empty : 10 Total Pages Marked Corrupt : 0 Total Pages Influx : 0 Total Pages Encrypted : 0 Highest block SCN : 2066716 (0.2066716) [oracle@rh6 ~]$
4、查看告警日志信息
告警日志：
dbv校验生成的日志：
Reading datafile '/u01/app/oracle/oradata/prod/users01.dbf' for corruption at rdba: 0x010000aa (file 4, block 170) Reread (file 4, block 170) found same corrupt data Corrupt Block Found TSN = 4, TSNAME = USERS RFN = 4, BLK = 170, RDBA = 16777386 OBJN = -1, OBJD = 75131, OBJECT = USERS, SUBOBJECT = SEGMENT OWNER = , SEGMENT TYPE = Temporary Segment Tue Jul 15 14:00:25 2014 Trace dumping is performing id=[cdmp_20140715140025] Tue Jul 15 14:00:25 2014 Errors in file /u01/app/oracle/diag/rdbms/prod/prod/trace/prod_m000_8954.trc (incident=121488): ORA-01578: ORACLE data block corrupted (file # 4, block # 170) ORA-01110: data file 4: '/u01/app/oracle/oradata/prod/users01.dbf' Hex dump of (file 4, block 176) in trace file /u01/app/oracle/diag/rdbms/prod/prod/incident/incdir_121443/prod_m000_8954_i121443_a.trc Corrupt block relative dba: 0x010000b0 (file 4, block 176) Bad header found during validation Data in bad block: type: 6 format: 2 rdba: 0x012020b0 last change scn: 0x2020.201e6219 seq: 0x1 flg: 0x04 spare1: 0x20 spare2: 0x20 spare3: 0x2020 consistency value in tail: 0x62190601 check value in block header: 0x2185 computed block checksum: 0x2020 Reread of blocknum=176, file=/u01/app/
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MySQL：初学者的基本技能Apr 18, 2025 am 12:24 AMMySQL适合初学者学习数据库技能。1.安装MySQL服务器和客户端工具。2.理解基本SQL查询，如SELECT。3.掌握数据操作：创建表、插入、更新、删除数据。4.学习高级技巧：子查询和窗口函数。5.调试和优化：检查语法、使用索引、避免SELECT*，并使用LIMIT。
MySQL：结构化数据和关系数据库Apr 18, 2025 am 12:22 AMMySQL通过表结构和SQL查询高效管理结构化数据，并通过外键实现表间关系。1.创建表时定义数据格式和类型。2.使用外键建立表间关系。3.通过索引和查询优化提高性能。4.定期备份和监控数据库确保数据安全和性能优化。
MySQL：解释的关键功能和功能Apr 18, 2025 am 12:17 AMMySQL是一个开源的关系型数据库管理系统，广泛应用于Web开发。它的关键特性包括：1.支持多种存储引擎，如InnoDB和MyISAM，适用于不同场景；2.提供主从复制功能，利于负载均衡和数据备份；3.通过查询优化和索引使用提高查询效率。
SQL的目的：与MySQL数据库进行交互Apr 18, 2025 am 12:12 AMSQL用于与MySQL数据库交互，实现数据的增、删、改、查及数据库设计。1）SQL通过SELECT、INSERT、UPDATE、DELETE语句进行数据操作；2）使用CREATE、ALTER、DROP语句进行数据库设计和管理；3）复杂查询和数据分析通过SQL实现，提升业务决策效率。
初学者的MySQL：开始数据库管理Apr 18, 2025 am 12:10 AMMySQL的基本操作包括创建数据库、表格，及使用SQL进行数据的CRUD操作。1.创建数据库：CREATEDATABASEmy_first_db;2.创建表格：CREATETABLEbooks(idINTAUTO_INCREMENTPRIMARYKEY,titleVARCHAR(100)NOTNULL,authorVARCHAR(100)NOTNULL,published_yearINT);3.插入数据：INSERTINTObooks(title,author,published_year)VA
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