I need to protect against a media crash and it is not so important to go back to specific periods of time for the database.   I have read the documentation on the Derby Admin guide but am still confused on the use of SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE.

 

From what it says, a copy of the last full backup, the archived logs, and the active logs are needed to restore.   I am a little confused here on the archived logs and the active logs.  

 

·         Is there something special that should be done with the archived logs?   Or is it that the log file location needs to be on another media?

·         When SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE is used, are all transactions from that point on logged forever until the next full backup is done?   Is this more expensive in terms of disk space usage than just doing an SYSCS_UTIL.SYSCS_BACKUP_DATABASE periodically

·         Is the difference between SYSCS_UTIL.SYSCS_BACKUP_DATABASE and SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE that with the SYSCS_UTIL.SYSCS_BACKUP_DATABASE I can restore to that point in time, but with SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE (assuming the backup and log files are on a separate media), that I can recover to the last transaction?

 

Another question is the time to perform a roll-forward recovery if SYSCS_UTIL.SYSCS_BACKUP_DATABASE_AND_ENABLE_LOG_ARCHIVE_MODE is used.   Might it not be better to just have a separate instance of Derby available and use database replication.  Would this not provide a fully functional database up to just about the last transaction so recovery would be a matter or copying the replicated database to the system and restarting?