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SHOWLOG

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Displays information about the log files associated with the DBEnvironment.

Scope

SQLUtil Only

SQLUtil Syntax

>> SHOWLOG DBEnvironment Name: DBEnvironmentName Maintenance Word: MaintenanceWord Connect? (y/n) (opt): { Y [es] N [o]}

Parameters

DBEnvironmentName

is the name of a DBEnvironment.

MaintenanceWord

is the Maintenance Word.

Description

  • This command lets you display the log file status within the DBEnvironment.

  • Use SHOWLOG to display general information about the log as a whole and specific information about individual log files.

  • The normal response to the prompt Connect? is Y, since connecting to the DBEnvironment will result in display of current status information. If you are not connected, SQLUtil does a static SHOWLOG, which examines only the log entries in the DBECon file, and does not report the number of free log pages available or tell whether the file is ready for backup. Static SHOWLOG is used immediately after restoring a DBEnvironment following a media failure, or in other cases when you cannot CONNECT to the DBEnvironment. The default response to the Connect? prompt is Y.

  • SHOWLOG displays the following general information about the log as a whole:

    Archive Mode

    ON or OFF. ON means that you are using archive logging.

    Log Sequence Number Containing Most Recent Archive Checkpoint

    Indicates the log file that was active at the time the last STOREONLINE command was issued. This information is useful to HP support engineering personnel when you are using archive logging. If archive mode is OFF, this number is 0.

    Current Sequence Number

    Indicates the log file that has most recently been written to or switched into.

    First Log Sequence Number Needed for Recovery

    Indicates the log file from which you should start the rollforward recovery process if it is needed. This information is useful only when you are using archive logging. If archive mode is OFF, this number is 0.

    Log Mode

    SINGLE or DUAL, indicating single log files or dual log files.

    Number of Free Log Blocks

    Indicates the total amount of log file space available in 512-byte blocks.

  • SHOWLOG displays the following specific information about each log file:

    First Log Name, Second Log Name

    Indicates the file name, group and account of the log file.

    First Log File Status, Second Log File Status

    Shows the usability status of each file.

    Log File Size

    Indicates the number of pages in the log file. If you choose an odd number of log file pages in the START DBE NEW, START DBE NEWLOG statements or in the ADDLOG command, the number is rounded up to an even number, which is displayed here.

    Log Identifier

    A number that identifies a specific log file that has been added to the DBEnvironment. If you are using dual logging, one identifier number identifies both files in the pair. Log identifier numbers are reused when log files are purged and others are added.

    Log Sequence Number

    A number that identifies a specific log file in an archive log sequence. Log sequence numbers are never reused.

    Log Backup Status

    Backup status of the file. The type of status shown depends on whether you have specified a dynamic or static SHOWLOG. These are shown below.

  • For a dynamic SHOWLOG, the types of backup status are as follows:

    Not Ready for Backup

    This is the current file, which is not full yet.

    Ready for Backup

    The file is full, and the DBE is now using a different file, so this one is ready to be stored with STORELOG.

    Backup is Done

    The file has already been backed up.

    Backup is Not Required

    The DBEnvironment is in nonarchive mode, so the file does not need to be backed up.

  • For a static SHOWLOG, the types of backup status are as follows:

    Backup is Required

    The file has not been backed up yet.

    Backup is Done

    The file has already been backed up.

    Backup is Not Required

    The DBEnvironment is in nonarchive mode, so the file does not need to be backed up.

  • For archive logging, SHOWLOG displays information about the log files needed for rollforward recovery. You begin rollforward recovery with a SETUPRECOVERY command, then you use RESTORELOG and RECOVERLOG for each log file that is to be applied, starting with the First Log Sequence Number Needed for Recovery.

  • The DBEnvironment can be in use when this command is executed.

Authorization

You must be the DBECreator, have SM capability, or supply the correct Maintenance Word to use this command.

Examples

   Dynamic SHOWLOG with archive logging



   >> showlog

   DBEnvironment Name: PartsDBE

   Maintenance Word:  Return  

   Connect (y/n) (opt): y





   Archive Mode:  ON

   Log Sequence Number Containing Most Recent Archive Checkpoint: 1

   Current Log Sequence Number: 1

   First Log Sequence Number Needed for Recovery: 1

   Log Mode is: Dual

   Number of Free Block(s): 340





   First Log Name: PARTSLG1.TESTDBE.HOME

   First Log File Status: Useable

   Second Log Name: PARTSLG2.TESTDBE.HOME

   Second Log File Status: Useable

   Log File Size:  256

   Log Identifier Is: 1

   Log Sequence Number: 1

   Log Backup Status: Not Ready for Backup





   Static SHOWLOG with nonarchive logging





   >> showlog

   DBEnvironment Name: PartsDBE

   Maintenance Word:  Return 

   Connect (y/n) (opt): n





   Archive Mode:  OFF

   Log Sequence Number Containing Most Recent Archive Checkpoint: 0

   Current Log Sequence Number: 1

   First Log Sequence Number Needed for Recovery: 0

   Log Mode is: Dual

   Number of Free Log Blocks: N/A





   First Log Name: PARTSLG1.TESTDBE.HOME

   First Log File Status: Useable

   Second Log Name: PARTSLG2.TESTDBE.HOME

   Second Log File Status: Useable

   Log File Size:  256

   Log Identifier Is: 1

   Log Sequence Number: 1

   Log Backup Status: Backup Is Not Required


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