揭密一致性读------之UNDO回滚链(五)

 gyj@OCM> select dbms_rowid.rowid_relative_fno(rowid),dbms_rowid.rowid_block_number(rowid),id,name from gyj;
DBMS_ROWID.ROWID_RELATIVE_FNO(ROWID) DBMS_ROWID.ROWID_BLOCK_NUMBER(ROWID)         ID NAME
------------------------------------ ------------------------------------ ---------- ----------
                                   7                                 6495          1 EEEEE  
sys@OCM> alter system dump datafile 7 block 6495;
Object id on Block  Y
seg/obj: 0x13344  csc: 0x00.c6c93d  itc: 2  flg: E  typ: 1 - DATA
     brn: 0  bdba: 0x1c01958 ver: 0x01 opc: 0
     inc: 0  exflg: 0
 Itl           Xid                  Uba         Flag  Lck        Scn/Fsc
0x01   0x0007.002.000039a5  0x00c14bec.0496.15  ----    1  fsc 0x0000.00000000
0x02   0x0004.01a.000039be  0x00c2aafd.0433.04  C---    0  scn 0x0000.00c6c938
bdba: 0x01c0195f
data_block_dump,data header at 0x2b035b568a64
===============
tsiz: 0x1f98
hsiz: 0x14
pbl: 0x2b035b568a64
     76543210
flag=--------
ntab=1
nrow=1
frre=-1
fsbo=0x14
fseo=0x17bf
avsp=0x17ab
tosp=0x17ab
0xe:pti[0]      nrow=1  offs=0
0x12:pri[0]     offs=0x17bf
block_row_dump:
tab 0, row 0, @0x17bf
tl: 2009 fb: --H-FL-- lb: 0x1  cc: 2
col  0: [ 2]  c1 02
col  1: [2000]
45 45 45 45 45 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
****************************************************************************************
Itl           Xid                  Uba         Flag  Lck        Scn/Fsc
0x01   0x0007.002.000039a5  0x00c14bec.0496.15  ----    1  fsc 0x0000.00000000
0x02   0x0004.01a.000039be  0x00c2aafd.0433.04  C---    0  scn 0x0000.00c6c938
******************************************************************************************
Uba:0x00c14bec.0496.15==>3号文件，84972号块
sys@OCM>  alter system dump datafile 3 block 84972;
UNDO BLK:  
xid: 0x0007.002.000039a5  seq: 0x496 cnt: 0x15  irb: 0x15  icl: 0x0   flg: 0x0000
 Rec Offset      Rec Offset      Rec Offset      Rec Offset      Rec Offset
---------------------------------------------------------------------------
0x01 0x1f60     0x02 0x1f00     0x03 0x1e50     0x04 0x1dd4     0x05 0x1d58     
0x06 0x1cdc     0x07 0x1c70     0x08 0x1bc0     0x09 0x1b54     0x0a 0x1aa4     
0x0b 0x19f4     0x0c 0x1988     0x0d 0x18d8     0x0e 0x185c     0x0f 0x17f0     
0x10 0x1740     0x11 0x16b8     0x12 0x162c     0x13 0x15c4     0x14 0x1574     
0x15 0x0ce8
*-----------------------------
* Rec #0x15  slt: 0x02  objn: 78660(0x00013344)  objd: 78660  tblspc: 7(0x00000007)
*       Layer:  11 (Row)   opc: 1   rci 0x00   
Undo type:  Regular undo    Begin trans    Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000Ext idx: 0
flg2: 0
*-----------------------------
uba: 0x00c14bec.0496.14 ctl max scn: 0x0000.00c6c5fb prv tx scn: 0x0000.00c6c607
txn start scn: scn: 0x0000.00c6c93a logon user: 90
prev brb: 12667873 prev bcl: 0
KDO undo record:
KTB Redo 
op: 0x04  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: L  itl: xid:  0x0002.01d.00004c55 uba: 0x00c0035d.050b.28
                      flg: C---    lkc:  0     scn: 0x0000.00c6c92a
Array Update of 1 rows: 
tabn: 0 slot: 0(0x0) flag: 0x2c lock: 0 ckix: 0
ncol: 2 nnew: 1 size: 0
KDO Op code:  21 row dependencies Disabled
  xtype: XAxtype KDO_KDOM2 flags: 0x00000080  bdba: 0x01c0195f  hdba: 0x01c0195a
itli: 1  ispac: 0  maxfr: 4858
vect = 3
col  1: [2000]
44 44 44 44 44 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
*********