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首页 / 关于v$transaction表used_urec字段的测试

关于v$transaction表used_urec字段的测试

原创 黄宸宁 2016-05-24
3073
最近有客户问到v$transaction表used_urec字段是什么意思，看了下官方文档关于v$transaction视图的介绍
V$TRANSACTION lists the active transactions in the system.
Column	Datatype	Description
ADDR	RAW(4 | 8)	Address of the transaction state object
XIDUSN	NUMBER	Undo segment number
XIDSLOT	NUMBER	Slot number
XIDSQN	NUMBER	Sequence number
UBAFIL	NUMBER	Undo block address (UBA) filenum
UBABLK	NUMBER	UBA block number
UBASQN	NUMBER	UBA sequence number
UBAREC	NUMBER	UBA record number
STATUS	VARCHAR2(16)	Status
START_TIME	VARCHAR2(20)	Start time (wall clock)
START_SCNB	NUMBER	Start system change number (SCN) base
START_SCNW	NUMBER	Start SCN wrap
START_UEXT	NUMBER	Start extent number
START_UBAFIL	NUMBER	Start UBA file number
START_UBABLK	NUMBER	Start UBA block number
START_UBASQN	NUMBER	Start UBA sequence number
START_UBAREC	NUMBER	Start UBA record number
SES_ADDR	RAW(4 | 8)	User session object address
FLAG	NUMBER	Flag
SPACE	VARCHAR2(3)	YES if a space transaction
RECURSIVE	VARCHAR2(3)	YES if a recursive transaction
NOUNDO	VARCHAR2(3)	YES if a no undo transaction
PTX	VARCHAR2(3)	YES if parallel transaction
NAME	VARCHAR2(256)	Name of a named transaction
PRV_XIDUSN	NUMBER	Previous transaction undo segment number
PRV_XIDSLT	NUMBER	Previous transaction slot number
PRV_XIDSQN	NUMBER	Previous transaction sequence number
PTX_XIDUSN	NUMBER	Rollback segment number of the parent XID
PTX_XIDSLT	NUMBER	Slot number of the parent XID
PTX_XIDSQN	NUMBER	Sequence number of the parent XID
DSCN-B	NUMBER	This column is obsolete and maintained for backward compatibility. The value of this column is always equal to the value in DSCN_BASE.
DSCN-W	NUMBER	This column is obsolete and maintained for backward compatibility. The value of this column is always equal to the value in DSCN_WRAP.
USED_UBLK	NUMBER	Number of undo blocks used
USED_UREC	NUMBER	Number of undo records used
LOG_IO	NUMBER	Logical I/O
PHY_IO	NUMBER	Physical I/O
CR_GET	NUMBER	Consistent gets
CR_CHANGE	NUMBER	Consistent changes
START_DATE	DATE	Start time (wall clock)
DSCN_BASE	NUMBER	Dependent SCN base
DSCN_WRAP	NUMBER	Dependent SCN wrap
START_SCN	NUMBER	Start SCN
DEPENDENT_SCN	NUMBER	Dependent SCN
XID	RAW(8)	Transaction XID
PRV_XID	RAW(8)	Previous transaction XID
PTX_XID	RAW(8)	Parent transaction XID

其中关于used_urec 的解释为number of undo records used，从字面意思来看，很容易理解为dml操作时影响的行数，但是实际上并非完全如此，下面通过对delete、insert、update操作做undo的相关dump来说明。
1. delete 操作
SQL> 
SQL> delete from test2 where rownum<10;
9 rows deleted.
SQL> 
SQL> 
SQL> select xidusn,xidslot,xidsqn,ubablk,ubafil,ubarec,used_ublk,used_urec from v$transaction;
    XIDUSN    XIDSLOT     XIDSQN     UBABLK     UBAFIL     UBAREC  USED_UBLK  USED_UREC
---------- ---------- ---------- ---------- ---------- ---------- ---------- ----------
         2          7        979       2609          3         49          1          9
SQL> 
SQL>  
SQL> 
SQL> 
SQL> ALTER SYSTEM DUMP UNDO BLOCK '_SYSSMU2_2996391332$' XID 2 7 979;
System altered.
SQL> 
SQL> 
SQL> oradebug setmypid;
Statement processed.
SQL> 
SQL> oradebug tracefile_name;
/u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_4755.trc
SQL> 
SQL> 


[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ cat /u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_4755.trc
Trace file /u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_4755.trc
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
ORACLE_HOME = /u01/app/oracle/product/11.2.0/db_1
System name:    Linux
Node name:      orl5.oracle.com
Release:        2.6.32-200.13.1.el5uek
Version:        #1 SMP Wed Jul 27 21:02:33 EDT 2011
Machine:        x86_64
VM name:        VMWare Version: 6
Instance name: ora11g
Redo thread mounted by this instance: 1
Oracle process number: 22
Unix process pid: 4755, image: oracle@orl5.oracle.com (TNS V1-V3)

*** 2016-05-23 16:05:20.311
*** SESSION ID:(133.65) 2016-05-23 16:05:20.311
*** CLIENT ID:() 2016-05-23 16:05:20.311
*** SERVICE NAME:(SYS$USERS) 2016-05-23 16:05:20.311
*** MODULE NAME:(sqlplus@orl5.oracle.com (TNS V1-V3)) 2016-05-23 16:05:20.311
*** ACTION NAME:() 2016-05-23 16:05:20.311
 
 
********************************************************************************
Undo Segment:  _SYSSMU2_2996391332$ (2)
xid: 0x0002.007.000003d3
Low Blk   :   (0, 0) 
High Blk  :   (4, 127) 
Object Id :   ALL 
Layer     :   ALL 
Opcode    :   ALL 
Level     :   2 
 
********************************************************************************
UNDO BLK:  Extent: 4   Block: 49   dba (file#, block#): 3,0x00000a31
xid: 0x0002.007.000003d3  seq: 0xa3  cnt: 0x31  irb: 0x31  icl: 0x0   flg: 0x0000
                                                 |—v$transaction.ubarec UBA record number
 
 
 Rec Offset      Rec Offset      Rec Offset      Rec Offset      Rec Offset
---------------------------------------------------------------------------
0x01 0x1f7c     0x02 0x1f10     0x03 0x1ea4     0x04 0x1e38     0x05 0x1d88     
0x06 0x1cd8     0x07 0x1c6c     0x08 0x1bf0     0x09 0x1b84     0x0a 0x1ad4     
0x0b 0x1a68     0x0c 0x19e0     0x0d 0x1984     0x0e 0x18d4     0x0f 0x1824     
0x10 0x1778     0x11 0x16c8     0x12 0x1618     0x13 0x156c     0x14 0x14c0     
0x15 0x1410     0x16 0x1388     0x17 0x1328     0x18 0x12a0     0x19 0x1240     
0x1a 0x11a4     0x1b 0x10f8     0x1c 0x102c     0x1d 0x0f44     0x1e 0x0edc     
0x1f 0x0e84     0x20 0x0dfc     0x21 0x0da0     0x22 0x0cf4     0x23 0x0c48     
0x24 0x0bc0     0x25 0x0b50     0x26 0x0aa4     0x27 0x0a1c     0x28 0x0988     
0x29 0x0884     0x2a 0x07ac     0x2b 0x06d8     0x2c 0x0600     0x2d 0x0528     
0x2e 0x0450     0x2f 0x0370     0x30 0x0298     0x31 0x01c0     
 
*-----------------------------
* Rec #0x31  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x30   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00a31.00a3.30
KDO Op code: IRP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 2  ispac: 0  maxfr: 4858
tabn: 0 slot: 8(0x8) size/delt: 79
fb: --H-FL-- lb: 0x0  cc: 14
null:
01234567890123456789012345678901234567890123456789012345678901234567890123456789
--N-----------
col  0: [ 3]  53 59 53
col  1: [ 7]  49 5f 43 44 45 46 32
col  2: *NULL*
col  3: [ 2]  c1 37
col  4: [ 2]  c1 37
col  5: [ 5]  49 4e 44 45 58
col  6: [ 7]  78 6f 09 11 0a 2f 0e
col  7: [ 7]  78 6f 09 11 0a 2f 0e
col  8: [19]  32 30 31 31 2d 30 39 2d 31 37 3a 30 39 3a 34 36 3a 31 33
col  9: [ 5]  56 41 4c 49 44
col 10: [ 1]  4e
col 11: [ 1]  4e
col 12: [ 1]  4e
col 13: [ 2]  c1 05
 
*-----------------------------
* Rec #0x30  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x2f   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00a31.00a3.2f
KDO Op code: IRP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 2  ispac: 0  maxfr: 4858
tabn: 0 slot: 7(0x7) size/delt: 78
fb: --H-FL-- lb: 0x0  cc: 14
null:
01234567890123456789012345678901234567890123456789012345678901234567890123456789
--N-----------
col  0: [ 3]  53 59 53
col  1: [ 6]  49 5f 49 4e 44 31
col  2: *NULL*
col  3: [ 2]  c1 2a
col  4: [ 2]  c1 2a
col  5: [ 5]  49 4e 44 45 58
col  6: [ 7]  78 6f 09 11 0a 2f 0e
col  7: [ 7]  78 6f 09 11 0a 2f 0e
col  8: [19]  32 30 31 31 2d 30 39 2d 31 37 3a 30 39 3a 34 36 3a 31 33
col  9: [ 5]  56 41 4c 49 44
col 10: [ 1]  4e
col 11: [ 1]  4e
col 12: [ 1]  4e
col 13: [ 2]  c1 05
 
*-----------------------------
* Rec #0x2f  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x2e   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00a31.00a3.2e
KDO Op code: IRP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 2  ispac: 0  maxfr: 4858
tabn: 0 slot: 6(0x6) size/delt: 88
fb: --H-FL-- lb: 0x0  cc: 14
null:
01234567890123456789012345678901234567890123456789012345678901234567890123456789
--N-----------
col  0: [ 3]  53 59 53
col  1: [16]  50 52 4f 58 59 5f 52 4f 4c 45 5f 44 41 54 41 24
col  2: *NULL*
col  3: [ 2]  c1 1a
col  4: [ 2]  c1 1a
col  5: [ 5]  54 41 42 4c 45
col  6: [ 7]  78 6f 09 11 0a 2f 0e
col  7: [ 7]  78 6f 09 11 0a 2f 0e
col  8: [19]  32 30 31 31 2d 30 39 2d 31 37 3a 30 39 3a 34 36 3a 31 33
col  9: [ 5]  56 41 4c 49 44
col 10: [ 1]  4e
col 11: [ 1]  4e
col 12: [ 1]  4e
col 13: [ 2]  c1 02
 
*-----------------------------
* Rec #0x2e  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x2d   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00a31.00a3.2d
KDO Op code: IRP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 2  ispac: 0  maxfr: 4858
tabn: 0 slot: 5(0x5) size/delt: 78
fb: --H-FL-- lb: 0x0  cc: 14
null:
01234567890123456789012345678901234567890123456789012345678901234567890123456789
--N-----------
col  0: [ 3]  53 59 53
col  1: [ 6]  49 5f 4f 42 4a 23
col  2: *NULL*
col  3: [ 2]  c1 04
col  4: [ 2]  c1 04
col  5: [ 5]  49 4e 44 45 58
col  6: [ 7]  78 6f 09 11 0a 2f 0e
col  7: [ 7]  78 6f 09 11 0a 2f 0e
col  8: [19]  32 30 31 31 2d 30 39 2d 31 37 3a 30 39 3a 34 36 3a 31 33
col  9: [ 5]  56 41 4c 49 44
col 10: [ 1]  4e
col 11: [ 1]  4e
col 12: [ 1]  4e
col 13: [ 2]  c1 05
 
*-----------------------------
* Rec #0x2d  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x2c   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00a31.00a3.2c
KDO Op code: IRP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 2  ispac: 0  maxfr: 4858
tabn: 0 slot: 4(0x4) size/delt: 81
fb: --H-FL-- lb: 0x0  cc: 14
null:
01234567890123456789012345678901234567890123456789012345678901234567890123456789
--N-----------
col  0: [ 3]  53 59 53
col  1: [ 7]  43 5f 43 4f 42 4a 23
col  2: *NULL*
col  3: [ 2]  c1 1e
col  4: [ 2]  c1 1e
col  5: [ 7]  43 4c 55 53 54 45 52
col  6: [ 7]  78 6f 09 11 0a 2f 0e
col  7: [ 7]  78 6f 09 11 0a 2f 0e
col  8: [19]  32 30 31 31 2d 30 39 2d 31 37 3a 30 39 3a 34 36 3a 31 33
col  9: [ 5]  56 41 4c 49 44
col 10: [ 1]  4e
col 11: [ 1]  4e
col 12: [ 1]  4e
col 13: [ 2]  c1 06
 
*-----------------------------
* Rec #0x2c  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x2b   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00a31.00a3.2b
KDO Op code: IRP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 2  ispac: 0  maxfr: 4858
tabn: 0 slot: 3(0x3) size/delt: 77
fb: --H-FL-- lb: 0x0  cc: 14
null:
01234567890123456789012345678901234567890123456789012345678901234567890123456789
--N-----------
col  0: [ 3]  53 59 53
col  1: [ 5]  55 4e 44 4f 24
col  2: *NULL*
col  3: [ 2]  c1 10
col  4: [ 2]  c1 10
col  5: [ 5]  54 41 42 4c 45
col  6: [ 7]  78 6f 09 11 0a 2f 0e
col  7: [ 7]  78 6f 09 11 0a 2f 0e
col  8: [19]  32 30 31 31 2d 30 39 2d 31 37 3a 30 39 3a 34 36 3a 31 33
col  9: [ 5]  56 41 4c 49 44
col 10: [ 1]  4e
col 11: [ 1]  4e
col 12: [ 1]  4e
col 13: [ 2]  c1 02
 
*-----------------------------
* Rec #0x2b  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x2a   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00a31.00a3.2a
KDO Op code: IRP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 2  ispac: 0  maxfr: 4858
tabn: 0 slot: 2(0x2) size/delt: 76
fb: --H-FL-- lb: 0x0  cc: 14
null:
01234567890123456789012345678901234567890123456789012345678901234567890123456789
--N-----------
col  0: [ 3]  53 59 53
col  1: [ 4]  43 4f 4e 24
col  2: *NULL*
col  3: [ 2]  c1 1d
col  4: [ 2]  c1 1d
col  5: [ 5]  54 41 42 4c 45
col  6: [ 7]  78 6f 09 11 0a 2f 0e
col  7: [ 7]  78 6f 09 11 0b 05 15
col  8: [19]  32 30 31 31 2d 30 39 2d 31 37 3a 30 39 3a 34 36 3a 31 33
col  9: [ 5]  56 41 4c 49 44
col 10: [ 1]  4e
col 11: [ 1]  4e
col 12: [ 1]  4e
col 13: [ 2]  c1 02
 
*-----------------------------
* Rec #0x2a  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x29   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00a31.00a3.29
KDO Op code: IRP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 2  ispac: 0  maxfr: 4858
tabn: 0 slot: 1(0x1) size/delt: 79
fb: --H-FL-- lb: 0x0  cc: 14
null:
01234567890123456789012345678901234567890123456789012345678901234567890123456789
--N-----------
col  0: [ 3]  53 59 53
col  1: [ 7]  49 5f 55 53 45 52 31
col  2: *NULL*
col  3: [ 2]  c1 2f
col  4: [ 2]  c1 2f
col  5: [ 5]  49 4e 44 45 58
col  6: [ 7]  78 6f 09 11 0a 2f 0e
col  7: [ 7]  78 6f 09 11 0a 2f 0e
col  8: [19]  32 30 31 31 2d 30 39 2d 31 37 3a 30 39 3a 34 36 3a 31 33
col  9: [ 5]  56 41 4c 49 44
col 10: [ 1]  4e
col 11: [ 1]  4e
col 12: [ 1]  4e
col 13: [ 2]  c1 05
 
*-----------------------------
* Rec #0x29  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       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: 0x00c00a31.00a3.28 ctl max scn: 0x0000.00149fc5 prv tx scn: 0x0000.00149fd9
txn start scn: scn: 0x0000.00000000 logon user: 90
 prev brb: 12585520 prev bcl: 0
KDO undo record:
KTB Redo 
op: 0x03  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: Z
KDO Op code: IRP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 2  ispac: 0  maxfr: 4858
tabn: 0 slot: 0(0x0) size/delt: 77
fb: --H-FL-- lb: 0x0  cc: 14
null:
01234567890123456789012345678901234567890123456789012345678901234567890123456789
--N-----------
col  0: [ 3]  53 59 53
col  1: [ 5]  49 43 4f 4c 24
col  2: *NULL*
col  3: [ 2]  c1 15
col  4: [ 2]  c1 03
col  5: [ 5]  54 41 42 4c 45
col  6: [ 7]  78 6f 09 11 0a 2f 0e
col  7: [ 7]  78 6f 09 11 0a 3b 01
col  8: [19]  32 30 31 31 2d 30 39 2d 31 37 3a 30 39 3a 34 36 3a 31 33
col  9: [ 5]  56 41 4c 49 44
col 10: [ 1]  4e
col 11: [ 1]  4e
col 12: [ 1]  4e
col 13: [ 2]  c1 02
 
 
+++++++++++ Next block not in extent map - rollback segment has been shrunk.
+ WARNING + Block dba (file#, block#): 0,0x00000000
+++++++++++
 
 
*************************************
Total undo blocks scanned  = 1 
Total undo records scanned = 9 
Total undo blocks dumped   = 1 
Total undo records dumped  = 9 
 
##Total warnings issued = 1 
*************************************
*** 2016-05-23 16:05:28.799
Processing Oradebug command 'setmypid'
*** 2016-05-23 16:05:28.800
Oradebug command 'setmypid' console output: <none>
*** 2016-05-23 16:05:36.698
Processing Oradebug command 'tracefile_name'
*** 2016-05-23 16:05:36.698
Oradebug command 'tracefile_name' console output: 
/u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_4755.trc
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ cat /u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_4755.trc|grep "Rec #"
* Rec #0x31  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x30  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x2f  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x2e  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x2d  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x2c  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x2b  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x2a  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x29  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
[oracle@orl5 ~]$

从上图可以看到当对表做delete操作删除9条数据后，查看v$transaction视图的used_urec字段显示的数据也是9，跟实际操作的行数是一致的，
在dump文件中，也能看到undo的记录数（* Rec #0x相关）也是9行，在每一个undo的记录中都能看到相关的delete删除表的记录信息
*-----------------------------
* Rec #0x30  slt: 0x07  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x2f   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00a31.00a3.2f
KDO Op code: IRP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 2  ispac: 0  maxfr: 4858
tabn: 0 slot: 7(0x7) size/delt: 78
fb: --H-FL-- lb: 0x0  cc: 14
null:
01234567890123456789012345678901234567890123456789012345678901234567890123456789
--N-----------
col  0: [ 3]  53 59 53
col  1: [ 6]  49 5f 49 4e 44 31
col  2: *NULL*
col  3: [ 2]  c1 2a
col  4: [ 2]  c1 2a
col  5: [ 5]  49 4e 44 45 58
col  6: [ 7]  78 6f 09 11 0a 2f 0e
col  7: [ 7]  78 6f 09 11 0a 2f 0e
col  8: [19]  32 30 31 31 2d 30 39 2d 31 37 3a 30 39 3a 34 36 3a 31 33
col  9: [ 5]  56 41 4c 49 44
col 10: [ 1]  4e
col 11: [ 1]  4e
col 12: [ 1]  4e
col 13: [ 2]  c1 05

2. insert操作
SQL> 
SQL> insert into test2 select * from dba_objects where rownum<50;
49 rows created.
SQL> 
SQL> 
SQL> select xidusn,xidslot,xidsqn,ubablk,ubafil,ubarec,used_ublk,used_urec from v$transaction;
    XIDUSN    XIDSLOT     XIDSQN     UBABLK     UBAFIL     UBAREC  USED_UBLK  USED_UREC
---------- ---------- ---------- ---------- ---------- ---------- ---------- ----------
         9         29       1068      31551          3         32          1          1
SQL> 
SQL> select s.usn,n.name,s.extents,s.hwmsize,s.status from v$rollstat s, v$rollname n where s.usn=n.usn;
       USN NAME                              EXTENTS    HWMSIZE STATUS
---------- ------------------------------ ---------- ---------- ---------------
         0 SYSTEM                                  6     385024 ONLINE
         1 _SYSSMU1_3724004606$                    5    2285568 ONLINE
         2 _SYSSMU2_2996391332$                    5    2285568 ONLINE
         3 _SYSSMU3_1723003836$                    5    3268608 ONLINE
         4 _SYSSMU4_1254879796$                    7     450560 ONLINE
         5 _SYSSMU5_898567397$                     4    2220032 ONLINE
         6 _SYSSMU6_1263032392$                    7     450560 ONLINE
         7 _SYSSMU7_2070203016$                   23   22142976 ONLINE
         8 _SYSSMU8_517538920$                     4     253952 ONLINE
         9 _SYSSMU9_1650507775$                   20   26337280 ONLINE
        10 _SYSSMU10_1197734989$                  10    7528448 ONLINE
11 rows selected.
SQL> 
SQL> 
SQL> 
SQL> ALTER SYSTEM DUMP UNDO BLOCK '_SYSSMU9_1650507775$' XID 9 29 1068;
System altered.
SQL> 
SQL> 
SQL> oradebug setmypid;
Statement processed.
SQL> 
SQL> 
SQL> oradebug tracefile_name;
/u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_4985.trc
SQL> 
SQL> 
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ cat /u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_4985.trc
Trace file /u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_4985.trc
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
ORACLE_HOME = /u01/app/oracle/product/11.2.0/db_1
System name:    Linux
Node name:      orl5.oracle.com
Release:        2.6.32-200.13.1.el5uek
Version:        #1 SMP Wed Jul 27 21:02:33 EDT 2011
Machine:        x86_64
VM name:        VMWare Version: 6
Instance name: ora11g
Redo thread mounted by this instance: 1
Oracle process number: 31
Unix process pid: 4985, image: oracle@orl5.oracle.com (TNS V1-V3)

*** 2016-05-23 16:31:56.910
*** SESSION ID:(192.69) 2016-05-23 16:31:56.910
*** CLIENT ID:() 2016-05-23 16:31:56.910
*** SERVICE NAME:(SYS$USERS) 2016-05-23 16:31:56.910
*** MODULE NAME:(sqlplus@orl5.oracle.com (TNS V1-V3)) 2016-05-23 16:31:56.910
*** ACTION NAME:() 2016-05-23 16:31:56.910
 
 
********************************************************************************
Undo Segment:  _SYSSMU9_1650507775$ (9)
xid: 0x0009.01d.0000042c
Low Blk   :   (0, 0) 
High Blk  :   (19, 127) 
Object Id :   ALL 
Layer     :   ALL 
Opcode    :   ALL 
Level     :   2 
 
********************************************************************************
UNDO BLK:  Extent: 18   Block: 63   dba (file#, block#): 3,0x00007b3f
xid: 0x0009.01d.0000042c  seq: 0x11b cnt: 0x20  irb: 0x20  icl: 0x0   flg: 0x0000
                                                |—v$transaction.ubarec UBA record number   
                                                   
 Rec Offset      Rec Offset      Rec Offset      Rec Offset      Rec Offset
---------------------------------------------------------------------------
0x01 0x1fa4     0x02 0x1f4c     0x03 0x1ec4     0x04 0x1e68     0x05 0x1db8     
0x06 0x1d4c     0x07 0x1c9c     0x08 0x1c30     0x09 0x1b80     0x0a 0x1ad4     
0x0b 0x1a28     0x0c 0x197c     0x0d 0x18d0     0x0e 0x1824     0x0f 0x1778     
0x10 0x16cc     0x11 0x1620     0x12 0x1574     0x13 0x14c8     0x14 0x1418     
0x15 0x139c     0x16 0x1330     0x17 0x12b4     0x18 0x1204     0x19 0x1154     
0x1a 0x10e8     0x1b 0x1038     0x1c 0x0f88     0x1d 0x0ed8     0x1e 0x0e28     
0x1f 0x0dbc     0x20 0x0ce8     
 
*-----------------------------
* Rec #0x20  slt: 0x1d  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       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: 0x00c07b3f.011b.1e ctl max scn: 0x0000.0014a0ad prv tx scn: 0x0000.0014a0b9
txn start scn: scn: 0x0000.0014a98b logon user: 90
 prev brb: 12614449 prev bcl: 0
KDO undo record:
KTB Redo 
op: 0x03  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: Z
KDO Op code: QMD row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x01000795  hdba: 0x0100020a
itli: 1  ispac: 0  maxfr: 4858
tabn: 0 lock: 0 nrow: 49       -----新插入的行记录
slot[0]: 0
slot[1]: 1
slot[2]: 2
slot[3]: 3
slot[4]: 4
slot[5]: 5
slot[6]: 6
slot[7]: 7
slot[8]: 8
slot[9]: 9
slot[10]: 10
slot[11]: 11
slot[12]: 12
slot[13]: 13
slot[14]: 14
slot[15]: 15
slot[16]: 16
slot[17]: 17
slot[18]: 18
slot[19]: 19
slot[20]: 20
slot[21]: 21
slot[22]: 22
slot[23]: 23
slot[24]: 24
slot[25]: 25
slot[26]: 26
slot[27]: 27
slot[28]: 28
slot[29]: 29
slot[30]: 30
slot[31]: 31
slot[32]: 32
slot[33]: 33
slot[34]: 34
slot[35]: 35
slot[36]: 36
slot[37]: 37
slot[38]: 38
slot[39]: 39
slot[40]: 40
slot[41]: 41
slot[42]: 42
slot[43]: 43
slot[44]: 44
slot[45]: 45
slot[46]: 46
slot[47]: 47
slot[48]: 48
 
 
+++++++++++ Next block not in extent map - rollback segment has been shrunk.
+ WARNING + Block dba (file#, block#): 0,0x00000000
+++++++++++
 
 
*************************************
Total undo blocks scanned  = 1 
Total undo records scanned = 1 
Total undo blocks dumped   = 1 
Total undo records dumped  = 1 
 
##Total warnings issued = 1 
*************************************
*** 2016-05-23 16:32:04.498
Processing Oradebug command 'setmypid'
*** 2016-05-23 16:32:04.498
Oradebug command 'setmypid' console output: <none>
*** 2016-05-23 16:32:11.642
Processing Oradebug command 'tracefile_name'
*** 2016-05-23 16:32:11.642
Oradebug command 'tracefile_name' console output: 
/u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_4985.trc
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ cat /u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_4985.trc|grep "Rec #"
* Rec #0x20  slt: 0x1d  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ cat /u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_4985.trc|grep "slot"|wc -l
49
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$

从上图可以看到当对表做insert操作插入了49条数据后，查看v$transaction视图的used_urec字段显示的数据只有1，跟实际操作的行数是不一致的，
在dump文件中，也只能看到undo的记录数（* Rec #0x相关）也只有1行，在这行记录里面记录下了所有insert的信息
*-----------------------------
* Rec #0x20  slt: 0x1d  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       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: 0x00c07b3f.011b.1e ctl max scn: 0x0000.0014a0ad prv tx scn: 0x0000.0014a0b9
txn start scn: scn: 0x0000.0014a98b logon user: 90
 prev brb: 12614449 prev bcl: 0
KDO undo record:
KTB Redo 
op: 0x03  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: Z
KDO Op code: QMD row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x01000795  hdba: 0x0100020a
itli: 1  ispac: 0  maxfr: 4858
tabn: 0 lock: 0 nrow: 49       -----新插入的行记录
slot[0]: 0
slot[1]: 1
slot[2]: 2
slot[3]: 3
slot[4]: 4
slot[5]: 5
slot[6]: 6
slot[7]: 7
slot[8]: 8
slot[9]: 9
slot[10]: 10
slot[11]: 11
slot[12]: 12
slot[13]: 13
slot[14]: 14
slot[15]: 15
slot[16]: 16
slot[17]: 17
slot[18]: 18
slot[19]: 19
slot[20]: 20
slot[21]: 21
slot[22]: 22
slot[23]: 23
slot[24]: 24
slot[25]: 25
slot[26]: 26
slot[27]: 27
slot[28]: 28
slot[29]: 29
slot[30]: 30
slot[31]: 31
slot[32]: 32
slot[33]: 33
slot[34]: 34
slot[35]: 35
slot[36]: 36
slot[37]: 37
slot[38]: 38
slot[39]: 39
slot[40]: 40
slot[41]: 41
slot[42]: 42
slot[43]: 43
slot[44]: 44
slot[45]: 45
slot[46]: 46
slot[47]: 47
slot[48]: 48

3. update操作
SQL> 
SQL> update test2 set object_name='TEST' where rownum<20;
19 rows updated.
SQL> 
SQL> 

SQL> 
SQL> set lines 200
SQL> 
SQL> 
SQL> select xidusn,xidslot,xidsqn,ubablk,ubafil,ubarec,used_ublk,used_urec from v$transaction;
    XIDUSN    XIDSLOT     XIDSQN     UBABLK     UBAFIL     UBAREC  USED_UBLK  USED_UREC
---------- ---------- ---------- ---------- ---------- ---------- ---------- ----------
         3         20       1014       2981          3         31          1         18
SQL> 
SQL> select s.usn,n.name,s.extents,s.hwmsize,s.status from v$rollstat s, v$rollname n where s.usn=n.usn;
       USN NAME                              EXTENTS    HWMSIZE STATUS
---------- ------------------------------ ---------- ---------- ---------------
         0 SYSTEM                                  6     385024 ONLINE
         1 _SYSSMU1_3724004606$                    5    2285568 ONLINE
         2 _SYSSMU2_2996391332$                    5    2285568 ONLINE
         3 _SYSSMU3_1723003836$                    5    3268608 ONLINE
         4 _SYSSMU4_1254879796$                    7     450560 ONLINE
         5 _SYSSMU5_898567397$                     4    2220032 ONLINE
         6 _SYSSMU6_1263032392$                    7     450560 ONLINE
         7 _SYSSMU7_2070203016$                   23   22142976 ONLINE
         8 _SYSSMU8_517538920$                     4     253952 ONLINE
         9 _SYSSMU9_1650507775$                   20   26337280 ONLINE
        10 _SYSSMU10_1197734989$                  10    7528448 ONLINE
11 rows selected.
SQL> 
SQL> 
SQL> 
SQL> 
SQL> ALTER SYSTEM DUMP UNDO BLOCK '_SYSSMU3_1723003836$' XID 3 20 1014;
System altered.
SQL> 
SQL> oradebug setmypid
Statement processed.
SQL> 
SQL> oradebug tracefile_name
/u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_5152.trc
SQL> 
SQL> 

[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ cat /u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_5152.trc
Trace file /u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_5152.trc
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
ORACLE_HOME = /u01/app/oracle/product/11.2.0/db_1
System name:    Linux
Node name:      orl5.oracle.com
Release:        2.6.32-200.13.1.el5uek
Version:        #1 SMP Wed Jul 27 21:02:33 EDT 2011
Machine:        x86_64
VM name:        VMWare Version: 6
Instance name: ora11g
Redo thread mounted by this instance: 1
Oracle process number: 32
Unix process pid: 5152, image: oracle@orl5.oracle.com (TNS V1-V3)

*** 2016-05-23 16:54:39.948
*** SESSION ID:(9.89) 2016-05-23 16:54:39.948
*** CLIENT ID:() 2016-05-23 16:54:39.948
*** SERVICE NAME:(SYS$USERS) 2016-05-23 16:54:39.948
*** MODULE NAME:(sqlplus@orl5.oracle.com (TNS V1-V3)) 2016-05-23 16:54:39.948
*** ACTION NAME:() 2016-05-23 16:54:39.948
 
 
********************************************************************************
Undo Segment:  _SYSSMU3_1723003836$ (3)
xid: 0x0003.014.000003f6
Low Blk   :   (0, 0) 
High Blk  :   (4, 127) 
Object Id :   ALL 
Layer     :   ALL 
Opcode    :   ALL 
Level     :   2 
 
********************************************************************************
UNDO BLK:  Extent: 4   Block: 37   dba (file#, block#): 3,0x00000ba5
xid: 0x0003.014.000003f6  seq: 0xe5  cnt: 0x1f  irb: 0x1f  icl: 0x0   flg: 0x0000
 
 Rec Offset      Rec Offset      Rec Offset      Rec Offset      Rec Offset
---------------------------------------------------------------------------
0x01 0x1f98     0x02 0x1f48     0x03 0x1ea4     0x04 0x1e1c     0x05 0x1dbc     
0x06 0x1d68     0x07 0x1d04     0x08 0x1c4c     0x09 0x1be0     0x0a 0x1b84     
0x0b 0x1b20     0x0c 0x1acc     0x0d 0x1a0c     0x0e 0x1980     0x0f 0x1914     
0x10 0x18b4     0x11 0x1838     0x12 0x17d0     0x13 0x1770     0x14 0x1710     
0x15 0x16b0     0x16 0x1650     0x17 0x15f0     0x18 0x154c     0x19 0x14ec     
0x1a 0x148c     0x1b 0x1410     0x1c 0x13b0     0x1d 0x1350     0x1e 0x12d4     
0x1f 0x1270     
 
*-----------------------------
* Rec #0x1f  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x1e   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.1e
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 27(0x1b) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 7
col  1: [11]  50 52 4f 58 59 5f 44 41 54 41 24
 
*-----------------------------
* Rec #0x1e  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x1d   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.1d
Array Update of 1 rows: 
tabn: 0 slot: 26(0x1a) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 0
KDO Op code:  21 row dependencies Disabled
  xtype: XAxtype KDO_KDOM2 flags: 0x00000080  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
vect = 4
col  1: [ 4]  43 4c 55 24
 
*-----------------------------
* Rec #0x1d  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x1c   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.1c
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 25(0x19) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 3
col  1: [ 7]  49 5f 55 4e 44 4f 32
 
*-----------------------------
* Rec #0x1c  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x1b   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.1b
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 24(0x18) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 1
col  1: [ 5]  49 5f 54 53 31
 
*-----------------------------
* Rec #0x1b  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x1a   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.1a
Array Update of 1 rows: 
tabn: 0 slot: 23(0x17) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 0
KDO Op code:  21 row dependencies Disabled
  xtype: XAxtype KDO_KDOM2 flags: 0x00000080  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
vect = 4
col  1: [ 4]  43 4f 4c 24
 
*-----------------------------
* Rec #0x1a  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x19   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.19
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 22(0x16) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 3
col  1: [ 7]  49 5f 46 49 4c 45 32
 
*-----------------------------
* Rec #0x19  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x18   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.18
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 21(0x15) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 1
col  1: [ 5]  43 5f 54 53 23
 
*-----------------------------
* Rec #0x18  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x17   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.17
Array Update of 2 rows: 
tabn: 0 slot: 19(0x13) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 0
KDO Op code:  21 row dependencies Disabled
  xtype: XAxtype KDO_KDOM2 flags: 0x00000080  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
vect = 4
col  1: [ 4]  49 4e 44 24
tabn: 0 slot: 20(0x14) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 0
KDO Op code:  21 row dependencies Disabled
  xtype: XAxtype KDO_KDOM2 flags: 0x00000080  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
vect = 4
col  1: [ 4]  53 45 47 24
 
*-----------------------------
* Rec #0x17  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x16   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.16
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 18(0x12) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 3
col  1: [ 7]  49 5f 43 44 45 46 34
 
*-----------------------------
* Rec #0x16  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x15   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.15
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 17(0x11) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 1
col  1: [ 5]  49 5f 54 53 23
 
*-----------------------------
* Rec #0x15  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x14   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.14
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 16(0x10) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 2
col  1: [ 6]  49 5f 4f 42 4a 33
 
*-----------------------------
* Rec #0x14  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x13   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.13
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 15(0xf) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 2
col  1: [ 6]  49 5f 43 4f 4e 31
 
*-----------------------------
* Rec #0x13  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x12   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.12
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 14(0xe) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 3
col  1: [ 7]  49 5f 46 49 4c 45 31
 
*-----------------------------
* Rec #0x12  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x11   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.11
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 13(0xd) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 10
col  1: [14]  49 5f 46 49 4c 45 23 5f 42 4c 4f 43 4b 23
 
*-----------------------------
* Rec #0x11  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x10   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.10
Array Update of 1 rows: 
tabn: 0 slot: 12(0xc) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 0
KDO Op code:  21 row dependencies Disabled
  xtype: XAxtype KDO_KDOM2 flags: 0x00000080  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
vect = 4
col  1: [ 4]  55 45 54 24
 
*-----------------------------
* Rec #0x10  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x0f   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.0f
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 11(0xb) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 1
col  1: [ 5]  46 49 4c 45 24
 
*-----------------------------
* Rec #0xf  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x0e   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.0e
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 10(0xa) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 16
col  1: [20]  49 5f 50 52 4f 58 59 5f 52 4f 4c 45 5f 44 41 54 41 24 5f 31
 
*-----------------------------
* Rec #0xe  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       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: 0x00c00ba5.00e5.04 ctl max scn: 0x0000.0014a065 prv tx scn: 0x0000.0014a083
txn start scn: scn: 0x0000.00000000 logon user: 90
 prev brb: 12585891 prev bcl: 0
KDO undo record:
KTB Redo 
op: 0x03  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: Z
KDO Op code: URP row dependencies Disabled
  xtype: XA flags: 0x00000000  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
tabn: 0 slot: 9(0x9) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 2
col  1: [ 6]  49 5f 4f 42 4a 35
 
 
+++++++++++ Next block not in extent map - rollback segment has been shrunk.
+ WARNING + Block dba (file#, block#): 0,0x00000000
+++++++++++
 
 
*************************************
Total undo blocks scanned  = 1 
Total undo records scanned = 18 
Total undo blocks dumped   = 1 
Total undo records dumped  = 18 
 
##Total warnings issued = 1 
*************************************
*** 2016-05-23 16:54:57.409
Processing Oradebug command 'setmypid'
*** 2016-05-23 16:54:57.409
Oradebug command 'setmypid' console output: <none>
*** 2016-05-23 16:55:05.167
Processing Oradebug command 'tracefile_name'
*** 2016-05-23 16:55:05.167
Oradebug command 'tracefile_name' console output: 
/u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_5152.trc
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ cat /u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_5152.trc|grep "Rec #"
* Rec #0x1f  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x1e  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x1d  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x1c  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x1b  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x1a  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x19  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x18  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x17  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x16  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x15  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x14  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x13  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x12  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x11  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0x10  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0xf  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
* Rec #0xe  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$  cat /u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_5152.trc|grep "Rec #"|wc -l
18
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ 
[oracle@orl5 ~]$ cat /u01/app/oracle/diag/rdbms/ora11g/ora11g/trace/ora11g_ora_5152.trc|grep "slot:"|wc -l
19
[oracle@orl5 ~]$

从上图可以看到当对表做update操作插入了19条数据后，查看v$transaction视图的used_urec字段显示的数据只有18，跟实际操作的行数是不一致的，
在dump文件中，也只能看到undo的记录数（* Rec #0x相关）也只有18行，但是通过slot检索其实是可以看到19行记录的，这又是什么情况喃，其实在仔细看了Rec的记录后就会发现其中一个Rec中有两条记录
*-----------------------------
* Rec #0x18  slt: 0x14  objn: 89055(0x00015bdf)  objd: 89055  tblspc: 4(0x00000004)
*       Layer:  11 (Row)   opc: 1   rci 0x17   
Undo type:  Regular undo   Last buffer split:  No 
Temp Object:  No 
Tablespace Undo:  No 
rdba: 0x00000000
*-----------------------------
KDO undo record:
KTB Redo 
op: 0x02  ver: 0x01  
compat bit: 4 (post-11) padding: 1
op: C  uba: 0x00c00ba5.00e5.17
Array Update of 2 rows: 
tabn: 0 slot: 19(0x13) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 0
KDO Op code:  21 row dependencies Disabled
  xtype: XAxtype KDO_KDOM2 flags: 0x00000080  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
vect = 4
col  1: [ 4]  49 4e 44 24
tabn: 0 slot: 20(0x14) flag: 0x2c lock: 0 ckix: 12
ncol: 14 nnew: 1 size: 0
KDO Op code:  21 row dependencies Disabled
  xtype: XAxtype KDO_KDOM2 flags: 0x00000080  bdba: 0x0100020b  hdba: 0x0100020a
itli: 3  ispac: 0  maxfr: 4858
vect = 4
col  1: [ 4]  53 45 47 24

从上面的信息中可以看到，在做insert和update操作的时候，实际操作的行记录是可能存放在同一个record中的，只有delete操作的时候才会放在各自的record中，也是为什么会看到v$transaction表used_urec字段记录的数字会跟实际操作的行数不一致的情况，当然其中是什么原理，这个只有更进一步的了解undo的管理机制才行，后续再做补充。
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