Know more about RBA redo block address

A “Redo Block Address” (RBA) describes a physical location within a redo log file. An RBA consists of the following:

Log sequence number
Block number within log file
Byte offset within block

The structure of the redo block address is given below :
1 – The number of the redo log.
[4 bytes]

2 – The block offset from the beginning of the redo log file.
[4 bytes]

3 – The byte offset within the block.
[2 bytes]

Log sequence number v$logmnr_contents.RBASQN
Block number within log file v$logmnr_contents.RBABLK
Byte offset within block v$logmnr_contents.RBABYTE
So in this case, RBA [0x19.2.10] maps to Log squence 25, Block number 2 with byte offset 16.
With this information you should be able to find the details from v$logmnr_contents.

In particular, the buffer header information includes two fields: low-RBA and high-SCN. The low-RBA field indicates the point in the redo-log corresponding to the block’s first update after it came into the buffer cache. The high-SCN field indicates the SCN of the last update to the block.

 (size = 8180, compat size = 8180, section max = 11, section in-use = 0,
  last-recid= 0, old-recno = 0, last-recno = 0)
 (extent = 1, blkno = 2, numrecs = 11)
THREAD #1 - status:0x2 flags:0x0 dirty:47
low cache rba:(0x37a.11c.0) on disk rba:(0x37a.151.0)
on disk scn: 0x0000.0045d2f2 12/19/2011 01:03:21
resetlogs scn: 0x0000.00080634 11/07/2011 04:08:50
heartbeat: 770246919 mount id: 2811012380
THREAD #2 - status:0x0 flags:0x0 dirty:0
low cache rba:(0x0.0.0) on disk rba:(0x0.0.0)
on disk scn: 0x0000.00000000 01/01/1988 00:00:00
resetlogs scn: 0x0000.00000000 01/01/1988 00:00:00
heartbeat: 0 mount id: 0






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