About Extract Checkpoints

Extract checkpoint positions are composed of read checkpoints in the data source and write checkpoints in the trail. The following is a sampling of checkpoint information displayed with the INFO EXTRACT command with the SHOWCH option. In this case, the data source is an Oracle RAC database cluster, so there is thread information included in the output. You can view past checkpoints by specifying the number of them that you want to view after the SHOWCH argument.

Example 13-1 INFO EXTRACT with SHOWCH

EXTRACT    JC108XT Last Started 2011-01-01 14:15   Status ABENDED
Checkpoint Lag       00:00:00 (updated 00:00:01 ago)
Log Read Checkpoint  File /orarac/oradata/racq/redo01.log
            2011-01-01 14:16:45  Thread 1, Seqno 47, RBA 68748800
Log Read Checkpoint  File /orarac/oradata/racq/redo04.log
            2011-01-01 14:16:19  Thread 2, Seqno 24, RBA 65657408

Current Checkpoint Detail:

Read Checkpoint #1

    Oracle RAC Redo Log
    Startup Checkpoint (starting position in data source):
        Thread #: 1
        Sequence #: 47
        RBA: 68548112
        Timestamp: 2011-01-01 13:37:51.000000
        SCN: 0.8439720
        Redo File: /orarac/oradata/racq/redo01.log
    
Recovery Checkpoint (position of oldest unprocessed transaction in data source):
        Thread #: 1
        Sequence #: 47
        RBA: 68748304
        Timestamp: 2011-01-01 14:16:45.000000
        SCN: 0.8440969
        Redo File: /orarac/oradata/racq/redo01.log

    Current Checkpoint (position of last record read in the data source):
        Thread #: 1
        Sequence #: 47
        RBA: 68748800
        Timestamp: 2011-01-01 14:16:45.000000
        SCN: 0.8440969
        Redo File: /orarac/oradata/racq/redo01.log

Read Checkpoint #2

    Oracle RAC Redo Log

    Startup Checkpoint(starting position in data source):
        Sequence #: 24
        RBA: 60607504
        Timestamp: 2011-01-01 13:37:50.000000
        SCN: 0.8439719
        Redo File: /orarac/oradata/racq/redo04.log

Recovery Checkpoint (position of oldest unprocessed transaction in data source):
        Thread #: 2
        Sequence #: 24
        RBA: 65657408
        Timestamp: 2011-01-01 14:16:19.000000
        SCN: 0.8440613
        Redo File: /orarac/oradata/racq/redo04.log

    Current Checkpoint (position of last record read in the data source):
        Thread #: 2
        Sequence #: 24
        RBA: 65657408
        Timestamp: 2011-01-01 14:16:19.000000
        SCN: 0.8440613
        Redo File: /orarac/oradata/racq/redo04.log

Write Checkpoint #1

    GGS Log Trail

    Current Checkpoint (current write position):

        Sequence #: 2
        RBA: 2142224
        Timestamp: 2011-01-01 14:16:50.567638
        Extract Trail: ./dirdat/eh

    Header:
        Version = 2
        Record Source = A
        Type = 6
        # Input Checkpoints = 2
        # Output Checkpoints = 1

    File Information:
        Block Size = 2048
        Max Blocks = 100
        Record Length = 2048
        Current Offset = 0

    Configuration:
        Data Source = 3
        Transaction Integrity = 1
        Task Type = 0

    Status:
        Start Time = 2011-01-01 14:15:14
        Last Update Time = 2011-01-01 14:16:50
        Stop Status = A
        Last Result = 400

See Internal Checkpoint Information for information about the internal information that starts with the Header entry in the SHOWCH output.