使用dbms_repair修复块损坏的具体示例
使用dbms_repair修复块损坏的具体示例:
SQL> create tablespace block datafile D:oracleoradataoracle9ilock.dbf size 5M;
Tablespace created
SQL> connect dlinger/dlingerConnected to Oracle9i Enterprise Edition Release 9.2.0.1.0
Connected as dlinger
QL> create table test tablespace block as select * from all_tables;
Table created
SQL> insert into test select * from test;
806 rows inserted
SQL> insert into test select * from test;
1612 rows inserted
SQL> insert into test select * from test;
3224 rows inserted
SQL> insert into test select * from test;
6448 rows inserted
SQL> insert into test select * from test;
insert into test select * from test
ORA-01653: 表DLINGER.TEST无法通过128(在表空间BLOCK中)扩展
SQL> commit;
Commit complete
SQL> select count(*) from test;
COUNT(*)----------
12896
SQL> create index i_test on test(table_name);
Index created
SQL> alter system checkpoint;
System altered
SQL> connect sys/sys as sysdba
已连接。
SQL> shutdown immediate
数据库已经关闭。
已经卸载数据库。
ORACLE 例程已经关闭。
--使用UltraEdit编辑block.dbf,修改几个字符
SQL> startupORACLE 例程已经启动。
Total System Global Area 72424008 bytesFixed Size 453192 bytes
Variable Size 46137344 bytes
Database Buffers 25165824 bytes
Redo Buffers 667648 bytes
数据库装载完毕。
数据库已经打开。
SQL> select count(*) from dlinger.test;
select count(*) from dlinger.test
*
ERROR 位于第 1 行:
ORA-01578: ORACLE 数据块损坏(文件号14,块号160)
ORA-01110: 数据文件 14: D:ORACLEORADATAORACLE9IBLOCK.DBF
用dbv检查:
C:Documents and Settingsduanl>dbv file=D:oracleoradataoracle9ilock.dbf
blocksize=8192
DBVERIFY: Release 9.2.0.1.0 - Production on 星期二 8月 24 19:58:15 2004
Copyright (c) 1982, 2002, Oracle Corporation. All rights reserved.
DBVERIFY - 验证正在开始 : FILE = D:oracleoradataoracle9ilock.dbf标记为损坏的页160
***
Corrupt block relative dba: 0x038000a0 (file 14, block 160)
Bad check value found during dbv:
Data in bad block -
type: 6 format: 2 rdba: 0x038000a0
last change scn: 0x0000.0035f5c2 seq: 0x1 易做图: 0x06
consistency value in tail: 0xf5c20601
check value in block header: 0x3681, computed block checksum: 0x5bb
spare1: 0x0, spare2: 0x0, spare3: 0x0
***
DBVERIFY - 验证完成
检查的页总数 :640处理的页总数(数据):510
失败的页总数(数据):0
处理的页总数(索引):0
失败的页总数(索引):0
处理的页总数(其它):9
处理的总页数 (段) : 0
失败的总页数 (段) : 0
空的页总数 :120
标记为损坏的总页数:1
汇入的页总数 :0
使用dbms_repair包1.创建管理表:
SQL> connect sys/sys as sysdba
Connected to Oracle9i Enterprise Edition Release 9.2.0.1.0
Connected as SYS
SQL> exec DBMS_REPAIR.ADMIN_TABLES(REPAIR_TABLE,1,1,USERS);
PL/SQL procedure successfully completed
SQL> exec DBMS_REPAIR.ADMIN_TABLES(ORPHAN_TABLE,2,1,USERS);
PL/SQL procedure successfully completed
2.检查坏块:dbms_repair.check_object
SQL> declare2 cc number;
3 begin
4 dbms_repair.check_object(schema_name => DLINGER,object_name => TEST,cor
rupt_count => cc);
5 dbms_output.put_line(a => to_char(cc));
6 end;
7 /
1
PL/SQL 过程已成功完成。
看到这里用dbms_repair.check,检查的结果corrupt_count=1,有一个块损坏,和dbv的结果一致。
check完之后,在我们刚在创建的REPAIR_TABLE中查看块损坏信息:
SQL> SELECT object_name, relative_file_id, block_id,marked_corrupt, corrupt_description, repair_description,2 CHECK_TIMESTAMP from repair_table;
OBJECT_NAME RELATIVE_FILE_ID BLOCK_ID MARKED_CORRUPT CORRUPT_DESCRIPTION REPAIR_DESCRIPTION CHECK_TIMESTAMP-------------- ---------------- ---------- -------------- --------------------- ---------------------------- ---------------
TEST 14 160 TRUE mark block software corrupt 2004-8-24 21:46
在这个table中,可以看到损坏的block的信息,这里的信息和我们用dbv得到的一致。我们这个实验是在9i下模拟的,我们注意看MARKED_CORRUPT的值,这里经过check_object后,已经标识为TRUE了。
所以可以直接进行第四步了。
按照oracle文档上的说法,在8i下,check_object只会检查坏块,MARKED_CORRUPT为false
需要使用第3步,fix_corrupt_blocks定位 ,修改MARKED_CORRUPT为true,同时更新CHECK_TIMESTAMP。
这里我们经过实验,确认在9i下跳过第3步,是完全可行的。
那么8i是否需要执行第三步,我没有实验过,但推测应该是不可以跳过的。
3.定位坏块:dbms_repair.fix_corrupt_blocks
只有将坏块信息写入定义的REPAIR_TABLE后,才能定位坏块。declare
cc number;
begin
dbms_repair.fix_corrupt_blocks(schema_name => DLINGER,object_name => TEST,fix_count => cc);
dbms_output.put_line(a => to_char(cc));
end;
4.跳过坏块:
我们前面虽然定位了坏块,但是,如果我们访问table:
SQL> select count(*) from dlinger.dbblock;
select count(*) from dlinger.dbblock
ORA-01578: ORACLE 数据块损坏(文件号14,块号154)ORA-01110: 数据文件 14: D:ORACLEORADATAORACLE9IBLOCK.DBF
还是会得到错误信息。这里需要用skip_corrupt_blocks来跳过坏块:
SQL> exec dbms_repair.skip_corrupt_blocks(schema_name => DLINGER,object_name => TEST,flags => 1);
PL/SQL procedure successfully completed
SQL> select count(*) from dlinger.test;
COUNT(*)----------
12850
丢失了12896-12850=46行数据。
5.处理index上的无效键值;dump_orphan_keys
declarecc number;
begin
dbms_repair.dump_orphan_keys(schema_name => DLINGER,object_name => I_TEST,object_type => 2,
repair_table_name => REPAIR_TABLE,orphan_table_name => ORPHAN_TABLE,key_count => CC);
end;
/
SQL> SELECT * FROM ORPHAN_TABLE;
SCHEMA_NAME INDEX_NAME IPART_NAME INDEX_ID TABLE_NAME PART_NAME TABLE_ID KEYROWID KEY DUMP_TIMESTAMP-------------- ----------- ------------ ---------- ----------- ---------- ---------- ---------------------- ------------------------------------------ --------------
DLINGER I_TEST 30258 TEST 30257 AAAHYxAOwAAAIADA0A *BAAAAAAMTE9HTU5SQ19HU0lJ/g 2004-8-25 22:1
DLINGER I_TEST 30258 TEST 30257 AAAHYxAOwAAAIADAsA *BAAAAAAMTE9HTU5SQ19HVExP/g 2004-8-25 22:1
..............................................
DLINGER I_TEST 30258 TEST 30257 AAAHYxAOwAAAIADB0A *BAAAAAAPTE9HTU5SX0xPQkZSQUck/g 2004-8-25 22:1DLINGER I_TEST 30258 TEST 30257 AAAHYxAOwAAAIADBYA *BAAAAAAMTE9HTU5SX1RZUEUk/g 2004-8-25 22:1
DLINGER I_TEST 30258 TEST 30257 AAAHYxAOwAAAIADAQA *BAAAAAALTE9HTU5SX1VJRCT+ 2004-8-25 22:1
DLINGER I_TEST 30258 TEST 30257 AAAHYxAOwAAAIADAoA *BAAAAAAMTE9HTU5SX1VTRVIk/g 2004-8-25 22:1