iX V6.5 (30391-90011)

662 AppendixG

Recovery and Logging Quick Reference

Recovery Quick Reference

• Should not be disabled if roll-back recovery must be used later because it will reset the

logging time stamp, therefore recovery cannot be performed. The database will be

considered correct and cannot be rolled back.

• Transactions are not lost during a start recovery operation because they are not held in

the memory buffer. (A start recovery operation must be performed after a system

failure.)

• When the roll-back process ﬁnishes, the RESTART option in user logging can be used or

a new logging cycle can be started. Remember to purge the log ﬁle before starting the

new logging cycle.

Roll-Back Flag Settings

The recommended settings for TurboIMAGE/XL ﬂags used for roll-back recovery are

shown in the following table. Note that the ﬂags change depending on whether you are

storing a database, running in production, or initiating a database recovery.

Recovery

• Without a database backup copy, recovery can be performed using DBUNLOAD (chained)

and DBLOAD to salvage all or most of a database.

Table G-2. Roll-Back Flag Settings

Flags True-Online Backup DBSTORE Production DBRECOV

Access Disabled/Enabled Disabled Enabled Disabled

AUTODEFER Disabled Disabled Disabled Disabled

Dumping Disabled Disabled Disabled Disabled

ILR Disabled Disabled Disabled Disabled

Logging Enabled Enabled Enabled Enabled

Recovery Disabled/Enabled Enabled Disabled Enabled

Roll-back Enabled Enabled Enabled Enabled