谈谈Oracle undo表空间(六)
ndex) opc: 22 rci 0x00
Undo type: Regular undo Last buffer split: No
Temp Object: No
Tablespace Undo: No
rdba: 0x00800c49
*-----------------------------
index undo for leaf key operations
KTB Redo
op: 0x02 ver: 0x01
op: C uba: 0x00800c49.0692.2f
Dump kdilk : itl=2, kdxlkflg=0x1 sdc=0 indexid=0x401029 block=0x0040f182
(kdxlpu): purge leaf row
key :(10): 06 c5 2b 5f 60 0d 0e 02 c1 1d
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...
*-----------------------------
* Rec #0x12 slt: 0x28 objn: 5141(0x00001415) objd: 5141 tblspc: 0(0x00000000)
* Layer: 10 (Index) opc: 22 rci 0x11
Undo type: Regular undo Last buffer split: No
Temp Object: No
Tablespace Undo: No
rdba: 0x00000000
*-----------------------------
index undo for leaf key operations
KTB Redo
op: 0x02 ver: 0x01
op: C uba: 0x00800c4a.0692.11
Dump kdilk : itl=3, kdxlkflg=0x1 sdc=0 indexid=0x402b51 block=0x00402b52
(kdxlpu): purge leaf row
key :(10): 02 c1 04 06 00 40 2b 2a 00 08
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*-----------------------------
* Rec #0x13 slt: 0x05 objn: 69998(0x0001116e) objd: 69998 tblspc: 10(0x0000000a)
* Layer: 11 (Row) opc: 1 rci 0x00
Undo type: Regular undo Begin trans Last buffer split: No
Temp Object: No
Tablespace Undo: No
rdba: 0x00000000
*-----------------------------
uba: 0x00800c4a.0692.10 ctl max scn: 0x0000.0116f8c0 prv tx scn: 0x0000.0116f8d8
txn start scn: scn: 0x0000.0117548c logon user: 0
prev brb: 8391750 prev bcl: 0
KDO undo record:
KTB Redo
op: 0x04 ver: 0x01
op: L itl: xid: 0x0009.00f.00000a96 uba: 0x0080019d.0670.22
flg: C--- lkc: 0 scn: 0x0000.0114e6a3
KDO Op code: URP row dependencies Disabled
xtype: XA flags: 0x00000000 bdba: 0x02000010 hdba: 0x0200000b
itli: 1 ispac: 0 maxfr: 4858
tabn: 0 slot: 0(0x0) flag: 0x2c lock: 0 ckix: 12
ncol: 2 nnew: 1 size: 2 www.2cto.com
col 1: [ 3] 61 2b 2b
End dump data blocks tsn: 1 file#: 2 minblk 3146 maxblk 3146
(10)怎么去读这个dump文件,查找那条有事务的记录呢 其实在上面undo地址Uba(undo block address)所指示的地址:0x00800c4a.0692.13,已经告诉我们了,0x00800c4a是16进制的地址,而13就是那条update的记录!我们单独把那条记录拿出来:
*-----------------------------
* Rec #0x13 slt: 0x05 objn: 69998(0x0001116e) objd: 69998 tblspc: 10(0x0000000a)
* Layer: 11 (Row) opc: 1 rci 0x00
Undo type: Regular undo Begin trans Last buffer split: No
Temp Object: No
Tablespace Undo: No
rdba: 0x00000000 www.2cto.com
*-----------------------------
uba: 0x00800c4a.0692.10 ctl max scn: 0x0000.0116f8c0 prv tx scn: 0x0000.0116f8d8
txn start scn: scn: 0x0000.0117548c logon user: 0
prev brb: 8391750 prev bcl: 0
KDO undo record:
KTB Redo
op: 0x04 ver: 0x01
op: L itl: xid: 0x0009.00f.00000a96 uba: 0x0080019d.0670.22
flg: C--- lkc: 0 scn: 0x0000.0114e6a3
KDO Op code: URP row dependencies Disabled
xtype: XA flags: 0x00000000 bdba: 0x02000010 hdba: 0x0200000b
itli: 1 ispac: 0 maxfr: 4858
tabn: 0 slot: 0(0x0) flag: 0x2c lock: 0 ckix: 12
ncol: 2 nnew: 1 size: 2
col 1: [ 3] 61 2b 2b
(11)对比session A dump出来的信息和从undo dump出来的信息:
--session A
col 1: [ 1] 61
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--undo
col 1: [ 3] 61 2b 2b
通过对比,可以发现session A的col1的值为61,undo里面的col1的值为61 2b 2b,把这2个值转换成ascii码:
SQL> select chr(to_number('61','xx')),chr