alert日志报以下提示：
1 Corrupt block relative dba: 0x04c20df1 (file 19, block 134641) 2 Fractured block found during backing up datafile 3 Data in bad block: 4 type: 40 format: 2 rdba: 0x04c20df1 5 last change scn: 0x0000.189926c6 seq: 0x2 flg: 0x04 6 spare1: 0x0 spare2: 0x0 spare3: 0x0 7 consistency value in tail: 0x26c52802 8 check value in block header: 0xd25a 9 computed block checksum: 0x28b1 10 Reread of blocknum=134641, file=/oradata/omsdb1/OMS_DATA12.dbf. found same corrupt data 11 Reread of blocknum=134641, file=/oradata/omsdb1/OMS_DATA12.dbf. found same corrupt data 12 Reread of blocknum=134641, file=/oradata/omsdb1/OMS_DATA12.dbf. found same corrupt data 13 Reread of blocknum=134641, file=/oradata/omsdb1/OMS_DATA12.dbf. found same corrupt data 14 Reread of blocknum=134641, file=/oradata/omsdb1/OMS_DATA12.dbf. found same corrupt data
根据上述信息得知19号数据文件的134641为坏块，可以使用DBV工具或者RMAN来检查坏块信息
dbv:
1 [oracle@ASZAAS-OMS01 ~]$ dbv file=/oradata/omsdb1/OMS_DATA12.dbf 2 3 DBVERIFY: Release 11.2.0.4.0 - Production on Fri Jun 29 10:57:30 2018 4 5 Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved. 6 7 DBVERIFY - Verification starting : FILE = /oradata/omsdb1/OMS_DATA12.dbf 8 Page 134641 is influx - most likely media corrupt 9 Corrupt block relative dba: 0x04c20df1 (file 19, block 134641) 10 Fractured block found during dbv: 11 Data in bad block: 12 type: 40 format: 2 rdba: 0x04c20df1 13 last change scn: 0x0000.189926c6 seq: 0x2 flg: 0x04 14 spare1: 0x0 spare2: 0x0 spare3: 0x0 15 consistency value in tail: 0x26c52802 16 check value in block header: 0xd25a 17 computed block checksum: 0x28b1 18 19 20 21 DBVERIFY - Verification complete 22 23 Total Pages Examined : 3932160 24 Total Pages Processed (Data) : 164199 25 Total Pages Failing (Data) : 0 26 Total Pages Processed (Index): 9003 27 Total Pages Failing (Index): 0 28 Total Pages Processed (Other): 3757308 29 Total Pages Processed (Seg) : 0 30 Total Pages Failing (Seg) : 0 31 Total Pages Empty : 1649 32 Total Pages Marked Corrupt : 1 33 Total Pages Influx : 1 34 Total Pages Encrypted : 0 35 Highest block SCN : 421782991 (0.421782991)
rman:
1 RMAN> backup validate datafile 19; 2 3 Starting backup at 29-JUN-18 4 using channel ORA_DISK_1 5 channel ORA_DISK_1: starting full datafile backup set 6 channel ORA_DISK_1: specifying datafile(s) in backup set 7 input datafile file number=00019 name=/oradata/omsdb1/OMS_DATA12.dbf 8 channel ORA_DISK_1: backup set complete, elapsed time: 00:08:16 9 List of Datafiles 10 ================= 11 File Status Marked Corrupt Empty Blocks Blocks Examined High SCN 12 ---- ------ -------------- ------------ --------------- ---------- 13 19 FAILED 0 1649 3932160 421804976 14 File Name: /oradata/omsdb1/OMS_DATA12.dbf 15 Block Type Blocks Failing Blocks Processed 16 ---------- -------------- ---------------- 17 Data 0 164199 18 Index 0 9001 19 Other 1 3757311 20 21 validate found one or more corrupt blocks 22 See trace file /u01/app/oracle/diag/rdbms/omsdb1/omsdb1/trace/omsdb1_ora_20078.trc for details 23 Finished backup at 29-JUN-18
可以根据文件号和块号查出损坏的是对象,表还是LOB segment
1 select tablespace_name,segment_type,owner,segment_name from dba_extents where file_id=19 and 134641 between block_id AND block_id + blocks - 1;
19是文件号,134641是block号
如果是对象，可以重建:
alter index indexname rebuild
如果是表，可以使用10231事件忽略坏块，然后使用CTAS方式重建表最后rename table，别忘记rebuild index
alter session SET EVENTS '10231 trace name context forever,level 10'; create table tab_new as select * from tab; rename tab to tab_bak; rename tab_new to new; alter index indexname rebuild; alter session SET EVENTS '10231 trace name context off';
如果损坏的是LOB segment,先找出segment信息:
select owner, segment_name, segment_type from dba_extents where file_id = 19 and 134641 between block_id and block_id + blocks - 1;
输出如下:
1 owner=OMSADMIN 2 segment_name=SYS_LOB0000087489C00007$$ 3 segment_type=LOBSEGMENT
找到表名和LOB字段：
1 select table_name, column_name from dba_lobs where segment_name = 'SYS_LOB0000087489C00007$$' and owner = 'OMSADMIN';
输出如下：
1 table_name = OMS_LOGINFOR 2 column_name = CONTENT
找到坏块的bad rowid,使用以下plsql脚本:
1 create table bad_rows (row_id ROWID,oracle_error_code number); 2 3 declare 4 n number; 5 error_code number; 6 bad_rows number := 0; 7 ora1578 EXCEPTION; 8 PRAGMA EXCEPTION_INIT(ora1578, -1578); 9 begin 10 for cursor_lob in (select rowid rid, &lob_column from &table_owner.&table_with_lob) loop 11 begin 12 n:=dbms_lob.instr(cursor_lob.&lob_column,hextoraw('889911')) ; 13 exception 14 when ora1578 then 15 bad_rows := bad_rows + 1; 16 insert into bad_rows values(cursor_lob.rid,1578); 17 commit; 18 when others then 19 error_code:=SQLCODE; 20 bad_rows := bad_rows + 1; 21 insert into bad_rows values(cursor_lob.rid,error_code); 22 commit; 23 end; 24 end loop; 25 dbms_output.put_line('Total Rows identified with errors in LOB column: '||bad_rows); 26 end; 27 /
Enter value for lob_column: CONTENT
Enter value for table_owner: OMSADMIN
Enter value for table_with_lob: OMS_LOGINFOR
可以查询bad rowid
select * from bad_rows; ROW_ID ORACLE_ERROR_CODE 1 AABIz+AATAAAf2jAAB 1578 2 AABIz+AATAAAf2zAAA -1555 3 AABIz+AATAAAf2zAAB -1555 4 AABIz+AATAAAf7kAAA -1555
更新空LOB字段来避免ORA-1578,ORA-26040,如果是CLOB类型，将empty_blob()改为empty_clob()
update &table_owner.&table_with_lob set &lob_column = empty_clob() where rowid in (select row_id from bad_rows);
将bad rowid lob块移到其他表空间:
1 alter table &table_owner.&table_with_lob move LOB (&lob_column) store as (tablespace &tablespace_name);
最后重建索引rebuild index