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Title: 35.ASSM segment header block  •  Size: 301555  •  Last Modified: Thu, 04 Feb 2010 15:48:32 GMT
35 PAGETABLE SEGMENT HEADER
 
  0 1 2 3 4 5 6 7 8 9 A B C D E F   Start dump data blocks tsn: 17 file#: 16 minblk 35 maxblk 35
00 231 022 003 004 23 00 00 045 C7 45 98 00 00 006 017 048   buffer tsn: 17 rdba: 0x04000023 (16/35)
10 8C 6A9 00 0010 00 00 00 0011 00 00 00 0012 F9 18 00 0413   HEADER scn: 0x0000.009845c7 seq: 0x01 flg: 0x04 tail: 0x45c72301
20 07 00 00 0014 81 03 00 0015 08 1C 00 0016 9C 0217 00 00   frmt: 0x02 chkval: 0x6a8c type: 0x23=PAGETABLE SEGMENT HEADER
30 80 03 00 0018 02 00 00 0019 08 00 00 0020 23 1C 00 0421   HHWM   Extent Control Header
40 F9 18 00 0422 65 00 00 0023 00 00 00 0024 02 1C 00 0025     -----------------------------------------------------------------
50 0026 0027 00 0028 00 00 00 0029 0030 00 00 00 80 03 00 0031   LHWM   Extent Header:: spare1: 0      spare2: 0      #extents: 897    #blocks: 7176 
60 02 00 00 0032 08 00 00 0033 23 1C 00 0434 F9 18 00 0435                     last map  0x040018f9  #maps: 7      offset: 668  
70 65 00 00 0036 00 00 00 0037 02 1C 00 0038 11 1C 00 0439         Highwater::  0x04001c23  ext#: 896    blk#: 2      ext size: 8    
80 11 1C 00 0440 00 00 00 00 00 00 00 00 00 00 00 00     #blocks in seg. hdr's freelists: 0    
90 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00     #blocks below: 7170 
A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00     mapblk  0x040018f9  offset: 101  
B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00                      Unlocked
C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00     --------------------------------------------------------
D0 01 00 00 00 00 08 00 0041 00 00 00 00 34 04 00 0042     Low HighWater Mark :
E0 00 00 00 0043 22 00 00 0444 01 00 00 00 1145 1C 00 0446         Highwater::  0x04001c23  ext#: 896    blk#: 2      ext size: 8    
F0 22 00 00 0447 00 00 00 0048 00 00 00 00 00 00 00 00     #blocks in seg. hdr's freelists: 0    
100 00 00 00 00 00 00 00 00 33 00 00 0049 B9 01 00 0450   Map header   #blocks below: 7170 
110 CD 7A 00 0051 00 00 00 2052 21 00 00 0453 08 00 00 0054   EXTENT   mapblk  0x040018f9  offset: 101  
120 29 00 00 04 08 00 00 00 31 00 00 04 08 00 00 00   MAP   Level 1 BMB for High HWM block: 0x04001c11
130 39 00 00 04 08 00 00 00 41 00 00 04 08 00 00 00     Level 1 BMB for Low HWM block: 0x04001c11
140 49 00 00 04 08 00 00 00 51 00 00 04 08 00 00 00     --------------------------------------------------------
150 59 00 00 04 08 00 00 00 61 00 00 04 08 00 00 00     Segment Type: 1 nl2: 1      blksz: 2048   fbsz: 0     
160 69 00 00 04 08 00 00 00 71 00 00 04 08 00 00 00     L2 Array start offset:  0x00000434
170 79 00 00 04 08 00 00 00 81 00 00 04 08 00 00 00     First Level 3 BMB:  0x00000000
180 89 00 00 04 08 00 00 00 91 00 00 04 08 00 00 00     L2 Hint for inserts:  0x04000022
190 99 00 00 04 08 00 00 00 A1 00 00 04 08 00 00 00     Last Level 1 BMB:  0x04001c11
1A0 A9 00 00 04 08 00 00 00 B1 00 00 04 08 00 00 00     Last Level II BMB:  0x04000022
1B0 B9 00 00 04 08 00 00 00 C1 00 00 04 08 00 00 00     Last Level III BMB:  0x00000000
1C0 C9 00 00 04 08 00 00 00 D1 00 00 04 08 00 00 00        Map Header:: next  0x040001b9  #extents: 51   obj#: 31437  flag: 0x20000000
1D0 D9 00 00 04 08 00 00 00 E1 00 00 04 08 00 00 00     Extent Map
1E0 E9 00 00 04 08 00 00 00 F1 00 00 04 08 00 00 00     -----------------------------------------------------------------
1F0 F9 00 00 04 08 00 00 00 01 01 00 04 08 00 00 00      0x04000021  length: 8    
200 09 01 00 04 08 00 00 00 11 01 00 04 08 00 00 00      0x04000029  length: 8    
210 19 01 00 04 08 00 00 00 21 01 00 04 08 00 00 00      0x04000031  length: 8    
220 29 01 00 04 08 00 00 00 31 01 00 04 08 00 00 00      0x04000039  length: 8    
230 39 01 00 04 08 00 00 00 41 01 00 04 08 00 00 00      0x04000041  length: 8    
240 49 01 00 04 08 00 00 00 51 01 00 04 08 00 00 00      0x04000049  length: 8    
250 59 01 00 04 08 00 00 00 61 01 00 04 08 00 00 00      0x04000051  length: 8    
260 69 01 00 04 08 00 00 00 71 01 00 04 08 00 00 00      0x04000059  length: 8    
270 79 01 00 04 08 00 00 00 81 01 00 04 08 00 00 00      0x04000061  length: 8    
280 89 01 00 04 08 00 00 00 91 01 00 04 08 00 00 00      0x04000069  length: 8    
290 99 01 00 04 08 00 00 00 A1 01 00 04 08 00 00 00      0x04000071  length: 8    
2A0 A9 01 00 04 08 00 00 00 B1 01 00 04 08 00 00 00      0x04000079  length: 8    
2B0 21 00 00 0455 24 00 00 0456 21 00 00 04 29 00 00 04   AUXILLARY    0x04000081  length: 8    
2C0 31 00 00 04 32 00 00 04 31 00 00 04 39 00 00 04   MAP    0x04000089  length: 8    
2D0 41 00 00 04 42 00 00 04 41 00 00 04 49 00 00 04      0x04000091  length: 8    
2E0 51 00 00 04 52 00 00 04 51 00 00 04 59 00 00 04      0x04000099  length: 8    
2F0 61 00 00 04 62 00 00 04 61 00 00 04 69 00 00 04      0x040000a1  length: 8    
300 71 00 00 04 72 00 00 04 71 00 00 04 79 00 00 04      0x040000a9  length: 8    
310 81 00 00 04 82 00 00 04 81 00 00 04 89 00 00 04      0x040000b1  length: 8    
320 91 00 00 04 92 00 00 04 91 00 00 04 99 00 00 04      0x040000b9  length: 8    
330 A1 00 00 04 A2 00 00 04 A1 00 00 04 A9 00 00 04      0x040000c1  length: 8    
340 B1 00 00 04 B2 00 00 04 B1 00 00 04 B9 00 00 04      0x040000c9  length: 8    
350 C1 00 00 04 C2 00 00 04 C1 00 00 04 C9 00 00 04      0x040000d1  length: 8    
360 D1 00 00 04 D2 00 00 04 D1 00 00 04 D9 00 00 04      0x040000d9  length: 8    
370 E1 00 00 04 E2 00 00 04 E1 00 00 04 E9 00 00 04      0x040000e1  length: 8    
380 F1 00 00 04 F2 00 00 04 F1 00 00 04 F9 00 00 04      0x040000e9  length: 8    
390 01 01 00 04 02 01 00 04 01 01 00 04 09 01 00 04      0x040000f1  length: 8    
3A0 11 01 00 04 12 01 00 04 11 01 00 04 19 01 00 04      0x040000f9  length: 8    
3B0 21 01 00 04 22 01 00 04 21 01 00 04 29 01 00 04      0x04000101  length: 8    
3C0 31 01 00 04 32 01 00 04 31 01 00 04 39 01 00 04      0x04000109  length: 8    
3D0 41 01 00 04 42 01 00 04 41 01 00 04 49 01 00 04      0x04000111  length: 8    
3E0 51 01 00 04 52 01 00 04 51 01 00 04 59 01 00 04      0x04000119  length: 8    
3F0 61 01 00 04 62 01 00 04 61 01 00 04 69 01 00 04      0x04000121  length: 8    
400 71 01 00 04 72 01 00 04 71 01 00 04 79 01 00 04      0x04000129  length: 8    
410 81 01 00 04 82 01 00 04 81 01 00 04 89 01 00 04      0x04000131  length: 8    
420 91 01 00 04 92 01 00 04 91 01 00 04 99 01 00 04      0x04000139  length: 8    
430 A1 01 00 04 A2 01 00 04 A1 01 00 04 A9 01 00 04      0x04000141  length: 8    
440 B1 01 00 04 B2 01 00 04 22 00 00 0457 00 00 00 00   II LEVEL    0x04000149  length: 8    
450 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   BMBs    0x04000151  length: 8    
460 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      0x04000159  length: 8    
470 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      0x04000161  length: 8    
480 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      0x04000169  length: 8    
490 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      0x04000171  length: 8    
4A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      0x04000179  length: 8    
4B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      0x04000181  length: 8    
4C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      0x04000189  length: 8    
4D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      0x04000191  length: 8    
4E0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      0x04000199  length: 8    
4F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      0x040001a1  length: 8    
500 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      0x040001a9  length: 8    
510 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      0x040001b1  length: 8    
520 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    
530 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00     Auxillary Map
540 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00     --------------------------------------------------------
550 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 0     :  L1 dba:  0x04000021 Data dba:  0x04000024
560 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 1     :  L1 dba:  0x04000021 Data dba:  0x04000029
570 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 2     :  L1 dba:  0x04000031 Data dba:  0x04000032
580 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 3     :  L1 dba:  0x04000031 Data dba:  0x04000039
590 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 4     :  L1 dba:  0x04000041 Data dba:  0x04000042
5A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 5     :  L1 dba:  0x04000041 Data dba:  0x04000049
5B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 6     :  L1 dba:  0x04000051 Data dba:  0x04000052
5C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 7     :  L1 dba:  0x04000051 Data dba:  0x04000059
5D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 8     :  L1 dba:  0x04000061 Data dba:  0x04000062
5E0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 9     :  L1 dba:  0x04000061 Data dba:  0x04000069
5F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 10    :  L1 dba:  0x04000071 Data dba:  0x04000072
600 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 11    :  L1 dba:  0x04000071 Data dba:  0x04000079
610 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 12    :  L1 dba:  0x04000081 Data dba:  0x04000082
620 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 13    :  L1 dba:  0x04000081 Data dba:  0x04000089
630 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 14    :  L1 dba:  0x04000091 Data dba:  0x04000092
640 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 15    :  L1 dba:  0x04000091 Data dba:  0x04000099
650 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 16    :  L1 dba:  0x040000a1 Data dba:  0x040000a2
660 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 17    :  L1 dba:  0x040000a1 Data dba:  0x040000a9
670 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 18    :  L1 dba:  0x040000b1 Data dba:  0x040000b2
680 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 19    :  L1 dba:  0x040000b1 Data dba:  0x040000b9
690 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 20    :  L1 dba:  0x040000c1 Data dba:  0x040000c2
6A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 21    :  L1 dba:  0x040000c1 Data dba:  0x040000c9
6B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 22    :  L1 dba:  0x040000d1 Data dba:  0x040000d2
6C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 23    :  L1 dba:  0x040000d1 Data dba:  0x040000d9
6D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 24    :  L1 dba:  0x040000e1 Data dba:  0x040000e2
6E0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 25    :  L1 dba:  0x040000e1 Data dba:  0x040000e9
6F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 26    :  L1 dba:  0x040000f1 Data dba:  0x040000f2
700 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 27    :  L1 dba:  0x040000f1 Data dba:  0x040000f9
710 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 28    :  L1 dba:  0x04000101 Data dba:  0x04000102
720 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 29    :  L1 dba:  0x04000101 Data dba:  0x04000109
730 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 30    :  L1 dba:  0x04000111 Data dba:  0x04000112
740 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 31    :  L1 dba:  0x04000111 Data dba:  0x04000119
750 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 32    :  L1 dba:  0x04000121 Data dba:  0x04000122
760 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 33    :  L1 dba:  0x04000121 Data dba:  0x04000129
770 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 34    :  L1 dba:  0x04000131 Data dba:  0x04000132
780 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 35    :  L1 dba:  0x04000131 Data dba:  0x04000139
790 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 36    :  L1 dba:  0x04000141 Data dba:  0x04000142
7A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 37    :  L1 dba:  0x04000141 Data dba:  0x04000149
7B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 38    :  L1 dba:  0x04000151 Data dba:  0x04000152
7C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 39    :  L1 dba:  0x04000151 Data dba:  0x04000159
7D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 40    :  L1 dba:  0x04000161 Data dba:  0x04000162
7E0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00      Extent 41    :  L1 dba:  0x04000161 Data dba:  0x04000169
7F0 00 00 00 00 00 00 00 00 00 00 00 00 01 23 C7 4558      Extent 42    :  L1 dba:  0x04000171 Data dba:  0x04000172
   Extent 43    :  L1 dba:  0x04000171 Data dba:  0x04000179
   Extent 44    :  L1 dba:  0x04000181 Data dba:  0x04000182
SQL>create table TEST.TABLE_ASSM    Extent 45    :  L1 dba:  0x04000181 Data dba:  0x04000189
(    Extent 46    :  L1 dba:  0x04000191 Data dba:  0x04000192
  OWNER          VARCHAR2(30) not null,    Extent 47    :  L1 dba:  0x04000191 Data dba:  0x04000199
  OBJECT_NAME    VARCHAR2(30) not null,    Extent 48    :  L1 dba:  0x040001a1 Data dba:  0x040001a2
  SUBOBJECT_NAME VARCHAR2(30),    Extent 49    :  L1 dba:  0x040001a1 Data dba:  0x040001a9
  OBJECT_ID      NUMBER not null,    Extent 50    :  L1 dba:  0x040001b1 Data dba:  0x040001b2
  DATA_OBJECT_ID NUMBER,   --------------------------------------------------------
  OBJECT_TYPE    VARCHAR2(18),  
  CREATED        DATE not null,    Second Level Bitmap block DBAs
  LAST_DDL_TIME  DATE not null,    --------------------------------------------------------
  TIMESTAMP      VARCHAR2(19),    DBA 1:   0x04000022
  STATUS         VARCHAR2(7),  
  TEMPORARY      VARCHAR2(1), End dump data blocks tsn: 17 file#: 16 minblk 35 maxblk 35
  GENERATED      VARCHAR2(1),  
  SECONDARY      VARCHAR2(1)  
)  
tablespace ASSM;  
 
SQL> insert into test.table_assm select * from all_objects;  
SQL>commit;  
SQL>select header_file, header_block from  dba_segments  
where owner='TEST' and segment_name='TABLE_ASSM';  
 
HEADER_FILE     HEADER_BLOCK        
16 35  
 
SQL>alter system checkpoint;  
SQL>alter system dump datafile 16  block 35;  
1
Block types.
type:0x23
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:0x04000023
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: 0x0000.009845C7
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:0x6A8C
10
spare3
11
spare1
12
spare2
13
RDBA of the last block of the extent map: 0x040018F9
14
Number  of  maps
#maps:7
15
Number of extents #extents:897
16
Number of  blocks  #blocks:7176
17
Auxillary Map start offset.
Offset:668
18
HHWM. Extent no.
Highwater: ext#: 896
19
HHWM. Block no.
 Highwater:  blk#: 2
20
HHWM. Extent size
Highwater: ext size:8
21
High high-water mark (HWM) .
Indicates the point above which no blocks have been formated.
The High HWM is the highest point in the last extent below which blocks are formatted.
Highwater: RDBA: 0x04001C23=> file- 16 block- 7203
22
Map block RDBA.
mapblk: 0x040018f9
23
Offset:101
24
#blocks in seg. hdr's freelists:0
25
#blocks below:7170
26
Disk Lock : Locked by xid  ( pointer to the rollback segment transaction table slot  -  Undoseg#.slot#.wrap):  xid:0x0000.000.00000000
27
Rollback segment
XID:undoseg
28
Refers to a slot in the transaction table XID:slot#
29
XID:wrap
30
Disk Lock \ Unlocked.
Unlocked
31
Low high-water mark. Extent no.
Highwater: ext#: 896
32
Low high-water mark. Block no.
Highwater:  blk#: 2
33
Low high-water mark. Extent size
 Highwater: extent size:8
34
Low high-water mark (LHWM).The Low HWM is the point up to which all the blocks are formatted - and above which there may be unformatted blocks.
Highwater: RDBA: 0x04001C23=> file- 16 block- 7203
35
Map block RDBA.
mapblk: 0x67115257
36
Offset:101
37
#blocks in seg. hdr's freelists:0
38
#blocks below:7170
39
Level 1 BMB for High HWM block: 0x04001c11
40
 Level 1 BMB for Low HWM block: 0x04001c11
41
Block size
blksz:2048
42
 L2 Array start offset:  0x00000434
 
43
First Level 3 BMB:  0x00000000
44
L2 hint specifies L2 BMB to search.
L2 Hint for inserts:  0x04000022
45
Last block for each level of the B-tree
46
Last Level 1 BMB:  0x04001c11
47
 Last Level II BMB:  0x04000022
48
 Last Level III BMB:  0x00000000
49
Number of extents in extent map.
Map Header:  #extents:51
50
Contains DBA information of the next block containing extent map information.
Map Header: next 0x:040001B9
51
Map Header: obj#:31437
52
Map Header: flag: 0x:20000000
?
53
Beginning RDBA : 0x04000021
54
 len : 8
Number of blocks associated with the extent
55
L1 dba:  0x04000021
56
Data dba (first data block of  extent):  0x04000024
57
 Second Level Bitmap block DBAs:  DBA 1:   0x04000022
 
58
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:0x45C72301