KTB Redo

KTB Redo records modifications to the transaction header of a block. The inverse operations are recorded in the undo segment

Each KTB Redo record has an operation type. Known codes include:

Numeric CodeAlphanumeric Code

Type 1 Operation (F)

The following is an example of a type 1 operation (F)

  KTB Redo
  op: 0x01  ver: 0x01
  op: F  xid:  0x0006.010.000001b1    uba: 0x008004f1.0151.0b

op: 0x01  ver: 0x01

opHexadecimal representation of operation code

The alphanumeric value of the operation code is output on the following line of the symbolic dump

op: F  xid:  0x0006.010.000001b1    uba: 0x008004f1.0151.0b

opAlphanumeric representation of undo operation code

xid Transaction ID. Format is usn#.slot#.wrap# Components are:

usn#Undo segment number
slot#Slot number in undo segment
wrap#Sequence number

uba Undo block address. Format is dba.seq#.rec# Components are:

dbaData block address of undo block
seq#Sequence number of undo block
rec#Record number within undo block

Type 5 Operation (R)

The following is an example of a type 5 operation (R)

KTB Redo
op: 0x05  ver: 0x01
op: R  itc: 2
 Itl           Xid                  Uba         Flag  Lck        Scn/Fsc
0x01   0x0009.020.000001e1  0x008002fc.0193.01  ----    1  fsc 0x0000.00000000
0x02   0x0009.000.000001e2  0x008002fb.0193.01  ----  363  fsc 0x0000.00000000
op: R  itc: 2

op: Operation code R

itc: Number (count) of ITL entries - in this case 2

ITL entries include the following columns

Itl ITL Slot number

Xid Transaction ID

Uba Undo byte address

Flag Flag - values currently unknown

Lck Number of rows locked by ITL entry

Scn/Fsc SCN or First SCN - context dependent