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Title: 18.Extent map block  •  Size: 196889  •  Last Modified: Thu, 04 Feb 2010 15:48:32 GMT
18 EXTENT MAP BLOCK
 
  0 1 2 3 4 5 6 7 8 9 A B C D E F   Start dump data blocks tsn: 16 file#: 15 minblk 1001 maxblk 1001
00 121 022 003 004 E9 03 C0 035 96 3C 93 00 00 006 017 048   buffer tsn: 16 rdba: 0x03c003e9 (15/1001)
10 7D 2E9 00 0010 63 00 00 0011 00 00 00 0012 93 7A 00 0013   Map Header scn: 0x0000.00933c96 seq: 0x01 flg: 0x04 tail: 0x3c961201
20 00 00 00 4014 EA 03 C0 0315 07 00 00 0016 F1 03 C0 03   frmt: 0x02 chkval: 0x2e7d type: 0x12=EXTENT MAP BLOCK
30 08 00 00 00 F9 03 C0 03 08 00 00 00 01 04 C0 03   EMB Dump:
40 08 00 00 00 09 04 C0 03 08 00 00 00 11 04 C0 03   Map Header:: next 0x00000000 #extents: 99 obj#: 31379 flag: 0x40000000
50 08 00 00 00 19 04 C0 03 08 00 00 00 21 04 C0 03   Extent Map
60 08 00 00 00 29 04 C0 03 08 00 00 00 31 04 C0 03   -----------------------------------------------------------------
70 08 00 00 00 39 04 C0 03 08 00 00 00 41 04 C0 03   0x03c003ea length: 7
80 08 00 00 00 49 04 C0 03 08 00 00 00 51 04 C0 03   0x03c003f1 length: 8
90 08 00 00 00 59 04 C0 03 08 00 00 00 61 04 C0 03   0x03c003f9 length: 8
A0 08 00 00 00 69 04 C0 03 08 00 00 00 71 04 C0 03   0x03c00401 length: 8
B0 08 00 00 00 79 04 C0 03 08 00 00 00 81 04 C0 03   0x03c00409 length: 8
C0 08 00 00 00 89 04 C0 03 08 00 00 00 91 04 C0 03   0x03c00411 length: 8
D0 08 00 00 00 99 04 C0 03 08 00 00 00 A1 04 C0 03   0x03c00419 length: 8
E0 08 00 00 00 A9 04 C0 03 08 00 00 00 B1 04 C0 03   0x03c00421 length: 8
F0 08 00 00 00 B9 04 C0 03 08 00 00 00 C1 04 C0 03   0x03c00429 length: 8
100 08 00 00 00 C9 04 C0 03 08 00 00 00 D1 04 C0 03   0x03c00431 length: 8
110 08 00 00 00 D9 04 C0 03 08 00 00 00 E1 04 C0 03   0x03c00439 length: 8
120 08 00 00 00 E9 04 C0 03 08 00 00 00 F1 04 C0 03   0x03c00441 length: 8
130 08 00 00 00 F9 04 C0 03 08 00 00 00 01 05 C0 03   0x03c00449 length: 8
140 08 00 00 00 09 05 C0 03 08 00 00 00 11 05 C0 03   0x03c00451 length: 8
150 08 00 00 00 19 05 C0 03 08 00 00 00 21 05 C0 03   0x03c00459 length: 8
160 08 00 00 00 29 05 C0 03 08 00 00 00 31 05 C0 03   0x03c00461 length: 8
170 08 00 00 00 39 05 C0 03 08 00 00 00 41 05 C0 03   0x03c00469 length: 8
180 08 00 00 00 49 05 C0 03 08 00 00 00 51 05 C0 03   0x03c00471 length: 8
190 08 00 00 00 59 05 C0 03 08 00 00 00 61 05 C0 03   0x03c00479 length: 8
1A0 08 00 00 00 69 05 C0 03 08 00 00 00 71 05 C0 03   Extent Map 0x03c00481 length: 8
1B0 08 00 00 00 79 05 C0 03 08 00 00 00 81 05 C0 03   0x03c00489 length: 8
1C0 08 00 00 00 89 05 C0 03 08 00 00 00 91 05 C0 03   0x03c00491 length: 8
1D0 08 00 00 00 99 05 C0 03 08 00 00 00 A1 05 C0 03   0x03c00499 length: 8
1E0 08 00 00 00 A9 05 C0 03 08 00 00 00 B1 05 C0 03   0x03c004a1 length: 8
1F0 08 00 00 00 B9 05 C0 03 08 00 00 00 C1 05 C0 03   0x03c004a9 length: 8
200 08 00 00 00 C9 05 C0 03 08 00 00 00 D1 05 C0 03   0x03c004b1 length: 8
210 08 00 00 00 D9 05 C0 03 08 00 00 00 E1 05 C0 03   0x03c004b9 length: 8
220 08 00 00 00 E9 05 C0 03 08 00 00 00 F1 05 C0 03   0x03c004c1 length: 8
230 08 00 00 00 F9 05 C0 03 08 00 00 00 01 06 C0 03   0x03c004c9 length: 8
240 08 00 00 00 09 06 C0 03 08 00 00 00 11 06 C0 03   0x03c004d1 length: 8
250 08 00 00 00 19 06 C0 03 08 00 00 00 21 06 C0 03   0x03c004d9 length: 8
260 08 00 00 00 29 06 C0 03 08 00 00 00 31 06 C0 03   0x03c004e1 length: 8
270 08 00 00 00 39 06 C0 03 08 00 00 00 41 06 C0 03   0x03c004e9 length: 8
280 08 00 00 00 49 06 C0 03 08 00 00 00 51 06 C0 03   0x03c004f1 length: 8
290 08 00 00 00 59 06 C0 03 08 00 00 00 61 06 C0 03   0x03c004f9 length: 8
2A0 08 00 00 00 69 06 C0 03 08 00 00 00 71 06 C0 03   0x03c00501 length: 8
2B0 08 00 00 00 79 06 C0 03 08 00 00 00 81 06 C0 03   0x03c00509 length: 8
2C0 08 00 00 00 89 06 C0 03 08 00 00 00 91 06 C0 03   0x03c00511 length: 8
2D0 08 00 00 00 99 06 C0 03 08 00 00 00 A1 06 C0 03   0x03c00519 length: 8
2E0 08 00 00 00 A9 06 C0 03 08 00 00 00 B1 06 C0 03   0x03c00521 length: 8
2F0 08 00 00 00 B9 06 C0 03 08 00 00 00 C1 06 C0 03   0x03c00529 length: 8
300 08 00 00 00 C9 06 C0 03 08 00 00 00 D1 06 C0 03   0x03c00531 length: 8
310 08 00 00 00 D9 06 C0 03 08 00 00 00 E1 06 C0 03   0x03c00539 length: 8
320 08 00 00 00 E9 06 C0 03 08 00 00 00 F1 06 C0 03   0x03c00541 length: 8
330 08 00 00 00 F9 06 C0 0317 08 00 00 0018 00 00 00 00   0x03c00549 length: 8
340 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00551 length: 8
350 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00559 length: 8
360 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00561 length: 8
370 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00569 length: 8
380 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00571 length: 8
390 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00579 length: 8
3A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00581 length: 8
3B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00589 length: 8
3C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00591 length: 8
3D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00599 length: 8
3E0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c005a1 length: 8
3F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c005a9 length: 8
400 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c005b1 length: 8
410 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c005b9 length: 8
420 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c005c1 length: 8
430 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c005c9 length: 8
440 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c005d1 length: 8
450 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c005d9 length: 8
460 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c005e1 length: 8
470 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c005e9 length: 8
480 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c005f1 length: 8
490 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c005f9 length: 8
4A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00601 length: 8
4B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00609 length: 8
4C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00611 length: 8
4D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00619 length: 8
4E0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00621 length: 8
4F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00629 length: 8
500 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00631 length: 8
510 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00639 length: 8
520 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00641 length: 8
530 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00649 length: 8
540 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00651 length: 8
550 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00659 length: 8
560 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00661 length: 8
570 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00669 length: 8
580 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00671 length: 8
590 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00679 length: 8
5A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00681 length: 8
5B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00689 length: 8
5C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00691 length: 8
5D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c00699 length: 8
5E0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c006a1 length: 8
5F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c006a9 length: 8
600 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c006b1 length: 8
610 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c006b9 length: 8
620 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c006c1 length: 8
630 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c006c9 length: 8
640 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c006d1 length: 8
650 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c006d9 length: 8
660 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c006e1 length: 8
670 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c006e9 length: 8
680 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c006f1 length: 8
690 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   0x03c006f9 length: 8
6A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  
6B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   End dump data blocks tsn: 16 file#: 15 minblk 1001 maxblk 1001
6C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
6D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
6E0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
6F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
700 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
710 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
720 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
730 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
740 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
750 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
760 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
770 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
780 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
790 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
7A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
7B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
7C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
7D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
7E0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
7F0 00 00 00 00 00 00 00 00 00 00 00 00 01 12 9619 3C    
 
RDBA of the last block of the extent map : 0x03c003e9 (62915561)  
SQL>select dbms_utility.data_block_address_file(62915561)as file_,  
dbms_utility.data_block_address_block(62915561) as block_ from dual;  
 
FILE_       BLOCK_      
15 1001  
 
SQL> alter system dump datafile 15 block 1001;  

1
Block types.
type:0x12
2
The format of the cache header was changed for Oracle8. Under Oracle8 and 9, the value is always 2. Previously, it was 1.
frmt:0x02
3
spare1
4
spare2
5
The tablespace relative database block address (RDBA). This is constructed from the tablespace
relative file number (10 bits), and the block number of the data block within that file (22 bits)
RDBA:0x03C003E9
6
The SCN at which the block was last changed. The low-order 4 bytes are called the SCN base, and the high-order 2 bytes are called the SCN wrap.
scn: 0x0000.00933c96
7
A sequence number incremented for each change to a block at the same SCN. If the sequence
number wraps, a new SCN must be allocated. The value 0xff is reserved. When present it
indicates that the block has been marked as corrupt by Oracle.
seq:0x01

8
Flag.
1 - virgin block
2 - last change to the block was for a cleanout operation
4 - checksum value is set
8 - temporary data
flg:0x04
9
An optional checksum of the block contents. When a block is written, the checksum is either cleared or set depending on the setting of the
db_block_checksum parameter. When a block is read, the checksum is verified if present and if the parameter is set to TRUE. Checksums are always
calculated and checked for blocks in the SYSTEM tablespace. The checksum is the XOR of all the other 2-byte pairs in the block. Thus when a block with a
checksum is checked, the XOR of all the 2-byte words in the block should be 0.
chkval: 0x2E7D
10
spare3
11
Number of extents in extent map.
Map Header: #extents: 99
12
Contains DBA information of the next block containing extent map information.
Map Header:next 0x:00000000
13
Map Header: obj#:31379
14
Map Header: flag: 0x:40000000
15
Beginning RDBA.
RDBA (extent#): 0x03C003EA
16
Number of blocks associated with the extent.
len : 7
17
RDBA (extent#): 0x03C006F9
18
len : 8
19
Tail is comprised of the low-order two bytes of the SCN base followed by the block type and the sequence number. The consistency
of the header and tail is checked whenever a block is read. This detects most block corruptions, in particular split blocks from hot backups.
tail:0x3c961201