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