oracle drop table purge无备份bbed恢复(3/3)

来源：这里教程网时间：2026-03-03 16:21:16 作者：

### 12. bbed恢复extent map
```c
SQL> alter system dump datafile 5 block 129;
System altered.
SQL> select value from v$diag_info where name='Default Trace File';
Default Trace File
/u01/app/oracle/diag/rdbms/enmo/enmo/trace/enmo_ora_36383.trc
grep -w 'Inst' /u01/app/oracle/diag/rdbms/enmo/enmo/trace/enmo_ora_36383.trc|awk '{print $1}'|xargs -n 1 ora_rdba|grep command|sed 's/dump command://g'
select value from v$diag_info where name='Default Trace File';
--outfile: /u01/app/oracle/diag/rdbms/enmo/enmo/trace/enmo_ora_36462.trc
grep -i 'Length:' /u01/app/oracle/diag/rdbms/enmo/enmo/trace/enmo_ora_36462.trc|grep -in 'Offset:'|sed 's/://g'|sed 's/0x//g'|awk '{print "select "$1 " as n_num,\47" $2 "\47 as n_dba," $4 " as n_len from dual union all"}'

#### extent map
set linesize 200 pagesize 9999
col dba_em_1 for a20
col dba_em_2 for a20
col n_len for a30
with new_ext as (
select 1 as n_num,'01400080' as n_dba,8 as n_len from dual union all
select 2 as n_num,'01400088' as n_dba,8 as n_len from dual union all
select 3 as n_num,'01400090' as n_dba,8 as n_len from dual union all
select 4 as n_num,'01400098' as n_dba,8 as n_len from dual union all
select 5 as n_num,'014000a0' as n_dba,8 as n_len from dual union all
select 6 as n_num,'014000a8' as n_dba,8 as n_len from dual union all
select 7 as n_num,'014000b0' as n_dba,8 as n_len from dual union all
select 8 as n_num,'014000b8' as n_dba,8 as n_len from dual union all
select 9 as n_num,'014000c0' as n_dba,8 as n_len from dual union all
select 10 as n_num,'014000c8' as n_dba,8 as n_len from dual union all
select 11 as n_num,'014000d0' as n_dba,8 as n_len from dual union all
select 12 as n_num,'014000d8' as n_dba,8 as n_len from dual union all
select 13 as n_num,'014000e0' as n_dba,8 as n_len from dual union all
select 14 as n_num,'014000e8' as n_dba,8 as n_len from dual union all
select 15 as n_num,'014000f0' as n_dba,8 as n_len from dual union all
select 16 as n_num,'014000f8' as n_dba,8 as n_len from dual union all
select 17 as n_num,'01400100' as n_dba,64 as n_len from dual union all
select 18 as n_num,'01400140' as n_dba,64 as n_len from dual union all
select 19 as n_num,'01400180' as n_dba,64 as n_len from dual union all
select 20 as n_num,'014001c0' as n_dba,64 as n_len from dual union all
select 21 as n_num,'01400200' as n_dba,64 as n_len from dual union all
select 22 as n_num,'01400240' as n_dba,64 as n_len from dual union all
select 23 as n_num,'01400280' as n_dba,64 as n_len from dual union all
select 24 as n_num,'014002c0' as n_dba,64 as n_len from dual union all
select 25 as n_num,'01400300' as n_dba,64 as n_len from dual union all
select 26 as n_num,'01400340' as n_dba,64 as n_len from dual union all
select 27 as n_num,'01400380' as n_dba,64 as n_len from dual union all
select 28 as n_num,'014003c0' as n_dba,64 as n_len from dual union all
select 29 as n_num,'01400400' as n_dba,64 as n_len from dual union all
select 30 as n_num,'01400440' as n_dba,64 as n_len from dual union all
select 31 as n_num,'01400480' as n_dba,64 as n_len from dual union all
select 32 as n_num,'014004c0' as n_dba,64 as n_len from dual union all
select 33 as n_num,'01400500' as n_dba,64 as n_len from dual union all
select 34 as n_num,'01400540' as n_dba,64 as n_len from dual union all
select 35 as n_num,'01400580' as n_dba,64 as n_len from dual union all
select 36 as n_num,'014005c0' as n_dba,64 as n_len from dual union all
select 37 as n_num,'01400600' as n_dba,64 as n_len from dual union all
select 38 as n_num,'01400640' as n_dba,64 as n_len from dual union all
select 39 as n_num,'01400680' as n_dba,64 as n_len from dual union all
select 40 as n_num,'014006c0' as n_dba,64 as n_len from dual union all
select 41 as n_num,'01400700' as n_dba,64 as n_len from dual union all
select 42 as n_num,'01400740' as n_dba,64 as n_len from dual union all
select 43 as n_num,'01400780' as n_dba,64 as n_len from dual union all
select 44 as n_num,'014007c0' as n_dba,64 as n_len from dual union all
select 45 as n_num,'01400800' as n_dba,64 as n_len from dual union all
select 46 as n_num,'01400840' as n_dba,64 as n_len from dual union all
select 47 as n_num,'01400880' as n_dba,64 as n_len from dual union all
select 48 as n_num,'014008c0' as n_dba,64 as n_len from dual union all
select 49 as n_num,'01400900' as n_dba,64 as n_len from dual union all
select 50 as n_num,'01400940' as n_dba,64 as n_len from dual union all
select 51 as n_num,'01400980' as n_dba,64 as n_len from dual union all
select 52 as n_num,'014009c0' as n_dba,64 as n_len from dual union all
select 53 as n_num,'01400a00' as n_dba,64 as n_len from dual union all
select 54 as n_num,'01400a40' as n_dba,64 as n_len from dual union all
select 55 as n_num,'01400a80' as n_dba,64 as n_len from dual union all
select 56 as n_num,'01400ac0' as n_dba,64 as n_len from dual union all
select 57 as n_num,'01400b00' as n_dba,64 as n_len from dual union all
select 58 as n_num,'01400b40' as n_dba,64 as n_len from dual union all
select 59 as n_num,'01400b80' as n_dba,64 as n_len from dual union all
select 60 as n_num,'01400bc0' as n_dba,64 as n_len from dual union all
select 61 as n_num,'01400c00' as n_dba,64 as n_len from dual union all
select 62 as n_num,'01400c40' as n_dba,64 as n_len from dual union all
select 63 as n_num,'01400c80' as n_dba,64 as n_len from dual union all
select 64 as n_num,'01400cc0' as n_dba,64 as n_len from dual union all
select 65 as n_num,'01400d00' as n_dba,64 as n_len from dual union all
select 66 as n_num,'01400d40' as n_dba,64 as n_len from dual union all
select 67 as n_num,'01400d80' as n_dba,64 as n_len from dual union all
select 68 as n_num,'01400dc0' as n_dba,64 as n_len from dual union all
select 69 as n_num,'01400e00' as n_dba,64 as n_len from dual union all
select 70 as n_num,'01400e40' as n_dba,64 as n_len from dual union all
select 71 as n_num,'01400e80' as n_dba,64 as n_len from dual union all
select 72 as n_num,'01400ec0' as n_dba,64 as n_len from dual union all
select 73 as n_num,'01400f00' as n_dba,64 as n_len from dual union all
select 74 as n_num,'01400f40' as n_dba,64 as n_len from dual
),
new_ext_temp as(
select 
 n_num,
 dbms_utility.data_block_address_file(TO_NUMBER(n_dba, 'XXXXXXXX')) file_id,
 dbms_utility.data_block_address_block(TO_NUMBER(n_dba,'XXXXXXXX')) block_id,
 'm /x '||substr(n_dba,7,2)||substr(n_dba,5,2) ||' offset '||to_char(280+(n_num-1)*8) dba_em_1,  
 'm /x '||substr(n_dba,3,2)||substr(n_dba,1,2) ||' offset '||to_char(280+(n_num-1)*8+2) dba_em_2,
 case when n_num<=16                        then  'm /x '||'0800'||' offset '||to_char(280+(n_num-1)*8+4)
      when n_num>16 and n_num<=16+63        then  'm /x '||'8000'||' offset '||to_char(280+(n_num-1)*8+4)
      when n_num>16+63 and n_num<=16+63+120 then  'm /x '||'0004'||' offset '||to_char(280+(n_num-1)*8+4)
      when n_num>16+63+120                  then  'm /x '||'0020'||' offset '||to_char(280+(n_num-1)*8+4)
      else '0'
 end as n_len
 from (select rownum n_num,n_dba from new_ext where n_num<=16 or mod(n_num,2)=1)
 )
select dba_em_1 from new_ext_temp where n_num>1
union all
select dba_em_2 from new_ext_temp where n_num>1
union all
select n_len from new_ext_temp where n_num>1
;

#### aux extmap
set linesize 200 pagesize 9999
col dba_em_1 for a20
col dba_em_2 for a20
col n_len for a30
with all_ext as (
select 1 as n_num,'01400080' as n_dba,8 as n_len from dual union all
select 2 as n_num,'01400088' as n_dba,8 as n_len from dual union all
select 3 as n_num,'01400090' as n_dba,8 as n_len from dual union all
select 4 as n_num,'01400098' as n_dba,8 as n_len from dual union all
select 5 as n_num,'014000a0' as n_dba,8 as n_len from dual union all
select 6 as n_num,'014000a8' as n_dba,8 as n_len from dual union all
select 7 as n_num,'014000b0' as n_dba,8 as n_len from dual union all
select 8 as n_num,'014000b8' as n_dba,8 as n_len from dual union all
select 9 as n_num,'014000c0' as n_dba,8 as n_len from dual union all
select 10 as n_num,'014000c8' as n_dba,8 as n_len from dual union all
select 11 as n_num,'014000d0' as n_dba,8 as n_len from dual union all
select 12 as n_num,'014000d8' as n_dba,8 as n_len from dual union all
select 13 as n_num,'014000e0' as n_dba,8 as n_len from dual union all
select 14 as n_num,'014000e8' as n_dba,8 as n_len from dual union all
select 15 as n_num,'014000f0' as n_dba,8 as n_len from dual union all
select 16 as n_num,'014000f8' as n_dba,8 as n_len from dual union all
select 17 as n_num,'01400100' as n_dba,64 as n_len from dual union all
select 18 as n_num,'01400140' as n_dba,64 as n_len from dual union all
select 19 as n_num,'01400180' as n_dba,64 as n_len from dual union all
select 20 as n_num,'014001c0' as n_dba,64 as n_len from dual union all
select 21 as n_num,'01400200' as n_dba,64 as n_len from dual union all
select 22 as n_num,'01400240' as n_dba,64 as n_len from dual union all
select 23 as n_num,'01400280' as n_dba,64 as n_len from dual union all
select 24 as n_num,'014002c0' as n_dba,64 as n_len from dual union all
select 25 as n_num,'01400300' as n_dba,64 as n_len from dual union all
select 26 as n_num,'01400340' as n_dba,64 as n_len from dual union all
select 27 as n_num,'01400380' as n_dba,64 as n_len from dual union all
select 28 as n_num,'014003c0' as n_dba,64 as n_len from dual union all
select 29 as n_num,'01400400' as n_dba,64 as n_len from dual union all
select 30 as n_num,'01400440' as n_dba,64 as n_len from dual union all
select 31 as n_num,'01400480' as n_dba,64 as n_len from dual union all
select 32 as n_num,'014004c0' as n_dba,64 as n_len from dual union all
select 33 as n_num,'01400500' as n_dba,64 as n_len from dual union all
select 34 as n_num,'01400540' as n_dba,64 as n_len from dual union all
select 35 as n_num,'01400580' as n_dba,64 as n_len from dual union all
select 36 as n_num,'014005c0' as n_dba,64 as n_len from dual union all
select 37 as n_num,'01400600' as n_dba,64 as n_len from dual union all
select 38 as n_num,'01400640' as n_dba,64 as n_len from dual union all
select 39 as n_num,'01400680' as n_dba,64 as n_len from dual union all
select 40 as n_num,'014006c0' as n_dba,64 as n_len from dual union all
select 41 as n_num,'01400700' as n_dba,64 as n_len from dual union all
select 42 as n_num,'01400740' as n_dba,64 as n_len from dual union all
select 43 as n_num,'01400780' as n_dba,64 as n_len from dual union all
select 44 as n_num,'014007c0' as n_dba,64 as n_len from dual union all
select 45 as n_num,'01400800' as n_dba,64 as n_len from dual union all
select 46 as n_num,'01400840' as n_dba,64 as n_len from dual union all
select 47 as n_num,'01400880' as n_dba,64 as n_len from dual union all
select 48 as n_num,'014008c0' as n_dba,64 as n_len from dual union all
select 49 as n_num,'01400900' as n_dba,64 as n_len from dual union all
select 50 as n_num,'01400940' as n_dba,64 as n_len from dual union all
select 51 as n_num,'01400980' as n_dba,64 as n_len from dual union all
select 52 as n_num,'014009c0' as n_dba,64 as n_len from dual union all
select 53 as n_num,'01400a00' as n_dba,64 as n_len from dual union all
select 54 as n_num,'01400a40' as n_dba,64 as n_len from dual union all
select 55 as n_num,'01400a80' as n_dba,64 as n_len from dual union all
select 56 as n_num,'01400ac0' as n_dba,64 as n_len from dual union all
select 57 as n_num,'01400b00' as n_dba,64 as n_len from dual union all
select 58 as n_num,'01400b40' as n_dba,64 as n_len from dual union all
select 59 as n_num,'01400b80' as n_dba,64 as n_len from dual union all
select 60 as n_num,'01400bc0' as n_dba,64 as n_len from dual union all
select 61 as n_num,'01400c00' as n_dba,64 as n_len from dual union all
select 62 as n_num,'01400c40' as n_dba,64 as n_len from dual union all
select 63 as n_num,'01400c80' as n_dba,64 as n_len from dual union all
select 64 as n_num,'01400cc0' as n_dba,64 as n_len from dual union all
select 65 as n_num,'01400d00' as n_dba,64 as n_len from dual union all
select 66 as n_num,'01400d40' as n_dba,64 as n_len from dual union all
select 67 as n_num,'01400d80' as n_dba,64 as n_len from dual union all
select 68 as n_num,'01400dc0' as n_dba,64 as n_len from dual union all
select 69 as n_num,'01400e00' as n_dba,64 as n_len from dual union all
select 70 as n_num,'01400e40' as n_dba,64 as n_len from dual union all
select 71 as n_num,'01400e80' as n_dba,64 as n_len from dual union all
select 72 as n_num,'01400ec0' as n_dba,64 as n_len from dual union all
select 73 as n_num,'01400f00' as n_dba,64 as n_len from dual union all
select 74 as n_num,'01400f40' as n_dba,64 as n_len from dual
),
aux_temp as(
select rownum n_num,n_dba L1_dba,n_dba data_dba from all_ext where n_num<=16 or mod(n_num,2)=1
),
aux_temp2 as(
select n_num,L1_dba,
lpad(replace(lower(to_char(to_number(data_dba,'XXXXXXXX')+1,'XXXXXXXX')),' ',''),8,'0') d_dba 
from aux_temp where n_num<=16 and mod(n_num,2)=1
union all
select n_num,(select L1_dba from aux_temp t where t.n_num=a.n_num-1) L1_dba,L1_dba d_dba
from aux_temp a where n_num<=16 and mod(n_num,2)=0
union all
select n_num,L1_dba,lpad(replace(lower(to_char(to_number(data_dba,'XXXXXXXX')+2,'XXXXXXXX')),' ',''),8,'0')
from aux_temp a where n_num>16
order by 1
)
select 'm /x '||substr(L1_dba,7,2)||substr(L1_dba,5,2) ||' offset '||to_char(2736+(n_num-1)*8) from aux_temp2 where n_num>1
union all
select 'm /x '||substr(L1_dba,3,2)||substr(L1_dba,1,2) ||' offset '||to_char(2736+(n_num-1)*8+2) from aux_temp2 where n_num>1
union all
select 'm /x '||substr(d_dba,7,2)||substr(d_dba,5,2) ||' offset '||to_char(2736+(n_num-1)*8+4) from aux_temp2 where n_num>1
union all
select 'm /x '||substr(d_dba,3,2)||substr(d_dba,1,2) ||' offset '||to_char(2736+(n_num-1)*8+6) from aux_temp2 where n_num>1;
 ```

### 13. 检查恢复情况
```c
alter system flush shared_pool;
alter system flush shared_pool;
alter system flush buffer_cache;
alter system flush buffer_cache;
select count(1) from hsql.drop_1 a;
COUNT(1)
----------
      1345
set linesize 200 pagesize 999
col OWNER for a10
col segment_name for a20
select OWNER,segment_name,extent_id,file_id,block_id,blocks from dba_extents where segment_name ='DROP_1' order by extent_id;
OWNER	   SEGMENT_NAME 	 EXTENT_ID    FILE_ID	BLOCK_ID     BLOCKS
---------- -------------------- ---------- ---------- ---------- ----------
HSQL	   DROP_1			 0	    5	     128	  8
```
### 14. 检查段头块extent map恢复情况
```c
XDUL>bmb
input fno: 5
input blk: 130
struct kcbh, 20 bytes			@0  
	ub1 type_kcbh			@0      	  0x23    
	ub1 frmt_kcbh			@1      	  0xa2    
	ub1 spare1_kcbh			@2      	  0x00 
	ub1 spare2_kcbh			@3      	  0x00 
	ub4 rdba_kcbh			@4      	  0x01400082
	ub4 bas_kcbh			@8      	  0x060a180c
	ub2 wrp_kcbh			@12     	  0x0000
	ub1 seq_kcbh			@14     	  0x01
	ub1 flg_kcbh			@15     	  0x04
	ub2 chkval_kcbh			@16     	  0x9a10
	ub2 spare3_kcbh			@18     	  0x0000
struct ech(Extent Control Header)	@36  
	ub4 extents_ech			@36      	  0x00000001
	ub4 blocks_ech			@40      	  0x00000008
	ub4 offset_ech			@44      	  0x00000a9c
	ub4 ext_ech			@48      	  0x00000001
	ub4 blk_ech			@52      	  0x00000080
	ub4 extsize_ech			@56      	  0x00000080
	ub4 hw_ech			@60      	  0x01400f80
	ub4 hwmapblk_ech		@64      	  0x00000000
	ub4 hwoffset_ech		@68      	  0x00000001
	ub4 hwblocksshf_ech		@72      	  0x00000000
	ub4 hwblksbelow_ech		@76      	  0x00000ebc
	ub4 lhwmext_ech			@92      	  0x0000002b
	ub4 lhwmblk_ech			@96      	  0x00000080
	ub4 lhwmextsize_ech		@100      	  0x00000080
	ub4 lhwm_ech			@104      	  0x01400f00
	ub4 lhwmapblk_ech		@108      	  0x00000000
	ub4 lhwoffset_ech		@112      	  0x0000002b
	ub4 lhwblocksshf_ech		@116      	  0x00000000
	ub4 lhwblksbelow_ech		@120      	  0x00000e80
	ub4 segtype_ech			@208      	  0x00000001
	ub4 blksz_ech			@212      	  0x00002000
	ub4 fbsz_echo			@216      	  0x00000000
	ub4 l2asoffset_ech		@220      	  0x00001434
	ub4 firstbmb3_echo		@224      	  0x00000000
	ub4 l2hfinsert_ech		@228      	  0x01400081
	ub4 nl2_echo			@232      	  0x00000001
	ub4 lastBMB1_echo		@236      	  0x01400f01
	ub4 lastBMB2_echo		@240      	  0x01400081
	ub4 lastBMB3_echo		@244      	  0x00000000
	ub4 mhnext_echo			@260      	  0x00000000
	ub4 mhext_echo			@264      	  0x00000001
	ub4 mhobj_ech			@272      	  0x00003627
	ub4 mhflag_ech			@276      	  0x10000000
struct em(Extent Map)			@280  
	ub4 dba_em[0]			@280      	  0x01400080
	ub4 len_em[0]			@284      	  0x00000008
	ub4 dba_em[1]			@288      	  0x01400088
	ub4 len_em[1]			@292      	  0x00000008
	ub4 dba_em[2]			@296      	  0x01400090
	ub4 len_em[2]			@300      	  0x00000008
	ub4 dba_em[3]			@304      	  0x01400098
	ub4 len_em[3]			@308      	  0x00000008
	ub4 dba_em[4]			@312      	  0x014000a0
	ub4 len_em[4]			@316      	  0x00000008
	ub4 dba_em[5]			@320      	  0x014000a8
	ub4 len_em[5]			@324      	  0x00000008
	ub4 dba_em[6]			@328      	  0x014000b0
	ub4 len_em[6]			@332      	  0x00000008
	ub4 dba_em[7]			@336      	  0x014000b8
	ub4 len_em[7]			@340      	  0x00000008
	ub4 dba_em[8]			@344      	  0x014000c0
	ub4 len_em[8]			@348      	  0x00000008
	ub4 dba_em[9]			@352      	  0x014000c8
	ub4 len_em[9]			@356      	  0x00000008
	ub4 dba_em[10]			@360      	  0x014000d0
	ub4 len_em[10]			@364      	  0x00000008
	ub4 dba_em[11]			@368      	  0x014000d8
	ub4 len_em[11]			@372      	  0x00000008
	ub4 dba_em[12]			@376      	  0x014000e0
	ub4 len_em[12]			@380      	  0x00000008
	ub4 dba_em[13]			@384      	  0x014000e8
	ub4 len_em[13]			@388      	  0x00000008
	ub4 dba_em[14]			@392      	  0x014000f0
	ub4 len_em[14]			@396      	  0x00000008
	ub4 dba_em[15]			@400      	  0x014000f8
	ub4 len_em[15]			@404      	  0x00000008
	ub4 dba_em[16]			@408      	  0x01400100
	ub4 len_em[16]			@412      	  0x00000080
	ub4 dba_em[17]			@416      	  0x01400180
	ub4 len_em[17]			@420      	  0x00000080
	ub4 dba_em[18]			@424      	  0x01400200
	ub4 len_em[18]			@428      	  0x00000080
	ub4 dba_em[19]			@432      	  0x01400280
	ub4 len_em[19]			@436      	  0x00000080
	ub4 dba_em[20]			@440      	  0x01400300
	ub4 len_em[20]			@444      	  0x00000080
	ub4 dba_em[21]			@448      	  0x01400380
	ub4 len_em[21]			@452      	  0x00000080
	ub4 dba_em[22]			@456      	  0x01400400
	ub4 len_em[22]			@460      	  0x00000080
	ub4 dba_em[23]			@464      	  0x01400480
	ub4 len_em[23]			@468      	  0x00000080
	ub4 dba_em[24]			@472      	  0x01400500
	ub4 len_em[24]			@476      	  0x00000080
	ub4 dba_em[25]			@480      	  0x01400580
	ub4 len_em[25]			@484      	  0x00000080
	ub4 dba_em[26]			@488      	  0x01400600
	ub4 len_em[26]			@492      	  0x00000080
	ub4 dba_em[27]			@496      	  0x01400680
	ub4 len_em[27]			@500      	  0x00000080
	ub4 dba_em[28]			@504      	  0x01400700
	ub4 len_em[28]			@508      	  0x00000080
	ub4 dba_em[29]			@512      	  0x01400780
	ub4 len_em[29]			@516      	  0x00000080
	ub4 dba_em[30]			@520      	  0x01400800
	ub4 len_em[30]			@524      	  0x00000080
	ub4 dba_em[31]			@528      	  0x01400880
	ub4 len_em[31]			@532      	  0x00000080
	ub4 dba_em[32]			@536      	  0x01400900
	ub4 len_em[32]			@540      	  0x00000080
	ub4 dba_em[33]			@544      	  0x01400980
	ub4 len_em[33]			@548      	  0x00000080
	ub4 dba_em[34]			@552      	  0x01400a00
	ub4 len_em[34]			@556      	  0x00000080
	ub4 dba_em[35]			@560      	  0x01400a80
	ub4 len_em[35]			@564      	  0x00000080
	ub4 dba_em[36]			@568      	  0x01400b00
	ub4 len_em[36]			@572      	  0x00000080
	ub4 dba_em[37]			@576      	  0x01400b80
	ub4 len_em[37]			@580      	  0x00000080
	ub4 dba_em[38]			@584      	  0x01400c00
	ub4 len_em[38]			@588      	  0x00000080
	ub4 dba_em[39]			@592      	  0x01400c80
	ub4 len_em[39]			@596      	  0x00000080
	ub4 dba_em[40]			@600      	  0x01400d00
	ub4 len_em[40]			@604      	  0x00000080
	ub4 dba_em[41]			@608      	  0x01400d80
	ub4 len_em[41]			@612      	  0x00000080
	ub4 dba_em[42]			@616      	  0x01400e00
	ub4 len_em[42]			@620      	  0x00000080
	ub4 dba_em[43]			@624      	  0x01400e80
	ub4 len_em[43]			@628      	  0x00000080
	ub4 dba_em[44]			@632      	  0x01400f00
	ub4 len_em[44]			@636      	  0x00000080
struct am(Auxillary Map)		@2736  
	ub4 fdba_am[0]			@2736      	  0x01400080
	ub4 datadba_am[0]		@2740      	  0x01400083
	ub4 fdba_am[1]			@2744      	  0x01400080
	ub4 datadba_am[1]		@2748      	  0x01400088
	ub4 fdba_am[2]			@2752      	  0x01400090
	ub4 datadba_am[2]		@2756      	  0x01400091
	ub4 fdba_am[3]			@2760      	  0x01400090
	ub4 datadba_am[3]		@2764      	  0x01400098
	ub4 fdba_am[4]			@2768      	  0x014000a0
	ub4 datadba_am[4]		@2772      	  0x014000a1
	ub4 fdba_am[5]			@2776      	  0x014000a0
	ub4 datadba_am[5]		@2780      	  0x014000a8
	ub4 fdba_am[6]			@2784      	  0x014000b0
	ub4 datadba_am[6]		@2788      	  0x014000b1
	ub4 fdba_am[7]			@2792      	  0x014000b0
	ub4 datadba_am[7]		@2796      	  0x014000b8
	ub4 fdba_am[8]			@2800      	  0x014000c0
	ub4 datadba_am[8]		@2804      	  0x014000c1
	ub4 fdba_am[9]			@2808      	  0x014000c0
	ub4 datadba_am[9]		@2812      	  0x014000c8
	ub4 fdba_am[10]			@2816      	  0x014000d0
	ub4 datadba_am[10]		@2820      	  0x014000d1
	ub4 fdba_am[11]			@2824      	  0x014000d0
	ub4 datadba_am[11]		@2828      	  0x014000d8
	ub4 fdba_am[12]			@2832      	  0x014000e0
	ub4 datadba_am[12]		@2836      	  0x014000e1
	ub4 fdba_am[13]			@2840      	  0x014000e0
	ub4 datadba_am[13]		@2844      	  0x014000e8
	ub4 fdba_am[14]			@2848      	  0x014000f0
	ub4 datadba_am[14]		@2852      	  0x014000f1
	ub4 fdba_am[15]			@2856      	  0x014000f0
	ub4 datadba_am[15]		@2860      	  0x014000f8
	ub4 fdba_am[16]			@2864      	  0x01400100
	ub4 datadba_am[16]		@2868      	  0x01400102
	ub4 fdba_am[17]			@2872      	  0x01400180
	ub4 datadba_am[17]		@2876      	  0x01400182
	ub4 fdba_am[18]			@2880      	  0x01400200
	ub4 datadba_am[18]		@2884      	  0x01400202
	ub4 fdba_am[19]			@2888      	  0x01400280
	ub4 datadba_am[19]		@2892      	  0x01400282
	ub4 fdba_am[20]			@2896      	  0x01400300
	ub4 datadba_am[20]		@2900      	  0x01400302
	ub4 fdba_am[21]			@2904      	  0x01400380
	ub4 datadba_am[21]		@2908      	  0x01400382
	ub4 fdba_am[22]			@2912      	  0x01400400
	ub4 datadba_am[22]		@2916      	  0x01400402
	ub4 fdba_am[23]			@2920      	  0x01400480
	ub4 datadba_am[23]		@2924      	  0x01400482
	ub4 fdba_am[24]			@2928      	  0x01400500
	ub4 datadba_am[24]		@2932      	  0x01400502
	ub4 fdba_am[25]			@2936      	  0x01400580
	ub4 datadba_am[25]		@2940      	  0x01400582
	ub4 fdba_am[26]			@2944      	  0x01400600
	ub4 datadba_am[26]		@2948      	  0x01400602
	ub4 fdba_am[27]			@2952      	  0x01400680
	ub4 datadba_am[27]		@2956      	  0x01400682
	ub4 fdba_am[28]			@2960      	  0x01400700
	ub4 datadba_am[28]		@2964      	  0x01400702
	ub4 fdba_am[29]			@2968      	  0x01400780
	ub4 datadba_am[29]		@2972      	  0x01400782
	ub4 fdba_am[30]			@2976      	  0x01400800
	ub4 datadba_am[30]		@2980      	  0x01400802
	ub4 fdba_am[31]			@2984      	  0x01400880
	ub4 datadba_am[31]		@2988      	  0x01400882
	ub4 fdba_am[32]			@2992      	  0x01400900
	ub4 datadba_am[32]		@2996      	  0x01400902
	ub4 fdba_am[33]			@3000      	  0x01400980
	ub4 datadba_am[33]		@3004      	  0x01400982
	ub4 fdba_am[34]			@3008      	  0x01400a00
	ub4 datadba_am[34]		@3012      	  0x01400a02
	ub4 fdba_am[35]			@3016      	  0x01400a80
	ub4 datadba_am[35]		@3020      	  0x01400a82
	ub4 fdba_am[36]			@3024      	  0x01400b00
	ub4 datadba_am[36]		@3028      	  0x01400b02
	ub4 fdba_am[37]			@3032      	  0x01400b80
	ub4 datadba_am[37]		@3036      	  0x01400b82
	ub4 fdba_am[38]			@3040      	  0x01400c00
	ub4 datadba_am[38]		@3044      	  0x01400c02
	ub4 fdba_am[39]			@3048      	  0x01400c80
	ub4 datadba_am[39]		@3052      	  0x01400c82
	ub4 fdba_am[40]			@3056      	  0x01400d00
	ub4 datadba_am[40]		@3060      	  0x01400d02
	ub4 fdba_am[41]			@3064      	  0x01400d80
	ub4 datadba_am[41]		@3068      	  0x01400d82
	ub4 fdba_am[42]			@3072      	  0x01400e00
	ub4 datadba_am[42]		@3076      	  0x01400e02
	ub4 fdba_am[43]			@3080      	  0x01400e80
	ub4 datadba_am[43]		@3084      	  0x01400e82
	ub4 fdba_am[44]			@3088      	  0x01400f00
	ub4 datadba_am[44]		@3092      	  0x01400f02
	ub4 slbbdba1_am			@5192      	  0x01400081
	ub4 tail_kcbh			@8188      	  0x180c2301
XDUL>
```
### 15. 根据exts计算blocks脚本
```c
set serveroutput on
DECLARE
   exts number;
   blocks number;
  BEGIN
   exts:=45;
   blocks:=0;
  	for i in 1..exts loop
  		if(i<=16) then blocks := blocks + 8;
  		elsif(i<=63+16) then blocks := blocks + 128;
  		elsif(i<=120+63+16) then blocks := blocks + 1024;
  		else 
  			blocks := blocks + 8192;
  		end if;
  	end loop;
  dbms_output.put_line('Total blocks: '||to_char(blocks));
  END;
  / 
Total blocks: 3840  --> F00
PL/SQL procedure successfully completed.
SQL>
```
### 16. 恢复段头块ext信息 
```c
#### 参考值
ub4 extents_ech		  @36    --num exts   45 --> 2d
ub4 blocks_ech		  @40    --num blks   F00
ub4 ext_ech		      @48    --exts - 1
ub4 hwoffset_ech		@68    --exts - 1
ub4 mhext_echo		  @264   --exts
####
d offset 36 count 12
d offset 40 count 12
d offset 48 count 12
d offset 68 count 12
d offset 264 count 12
m /x 2d offset 36
m /x 00f0 offset 40
m /x 2c offset 48
m /x 2c offset 48
m /x 2d offset 264
```
### 17. 检查恢复情况
```c
SQL> alter system flush shared_pool;
alter system flush shared_pool;
alter system flush buffer_cache;
alter system flush buffer_cache;
select count(1) from hsql.drop_1 a;
System altered.
SQL> 
System altered.
SQL> 
System altered.
SQL> 
System altered.
SQL> 
  COUNT(1)
----------
   1000000
SQL> set linesize 200 pagesize 999
col OWNER for a10
col segment_name for a20
select OWNER,segment_name,extent_id,file_id,block_id,blocks from dba_extents where segment_name ='DROP_1' order by extent_id;SQL> SQL> SQL> 
OWNER	   SEGMENT_NAME 	 EXTENT_ID    FILE_ID	BLOCK_ID     BLOCKS
---------- -------------------- ---------- ---------- ---------- ----------
HSQL	   DROP_1			 0	    5	     128	  8
HSQL	   DROP_1			 1	    5	     136	  8
HSQL	   DROP_1			 2	    5	     144	  8
HSQL	   DROP_1			 3	    5	     152	  8
HSQL	   DROP_1			 4	    5	     160	  8
HSQL	   DROP_1			 5	    5	     168	  8
HSQL	   DROP_1			 6	    5	     176	  8
HSQL	   DROP_1			 7	    5	     184	  8
HSQL	   DROP_1			 8	    5	     192	  8
HSQL	   DROP_1			 9	    5	     200	  8
HSQL	   DROP_1			10	    5	     208	  8
HSQL	   DROP_1			11	    5	     216	  8
HSQL	   DROP_1			12	    5	     224	  8
HSQL	   DROP_1			13	    5	     232	  8
HSQL	   DROP_1			14	    5	     240	  8
HSQL	   DROP_1			15	    5	     248	  8
HSQL	   DROP_1			16	    5	     256	128
HSQL	   DROP_1			17	    5	     384	128
HSQL	   DROP_1			18	    5	     512	128
HSQL	   DROP_1			19	    5	     640	128
HSQL	   DROP_1			20	    5	     768	128
HSQL	   DROP_1			21	    5	     896	128
HSQL	   DROP_1			22	    5	    1024	128
HSQL	   DROP_1			23	    5	    1152	128
HSQL	   DROP_1			24	    5	    1280	128
HSQL	   DROP_1			25	    5	    1408	128
HSQL	   DROP_1			26	    5	    1536	128
HSQL	   DROP_1			27	    5	    1664	128
HSQL	   DROP_1			28	    5	    1792	128
HSQL	   DROP_1			29	    5	    1920	128
HSQL	   DROP_1			30	    5	    2048	128
HSQL	   DROP_1			31	    5	    2176	128
HSQL	   DROP_1			32	    5	    2304	128
HSQL	   DROP_1			33	    5	    2432	128
HSQL	   DROP_1			34	    5	    2560	128
HSQL	   DROP_1			35	    5	    2688	128
HSQL	   DROP_1			36	    5	    2816	128
HSQL	   DROP_1			37	    5	    2944	128
HSQL	   DROP_1			38	    5	    3072	128
HSQL	   DROP_1			39	    5	    3200	128
HSQL	   DROP_1			40	    5	    3328	128
HSQL	   DROP_1			41	    5	    3456	128
HSQL	   DROP_1			42	    5	    3584	128
HSQL	   DROP_1			43	    5	    3712	128
HSQL	   DROP_1			44	    5	    3840	128
45 rows selected.
SQL>
```