Decoupled virtual backups

If the system-level backup is done outside the backup transaction, the IQ store backup will not be consistent with the IQ backup file. However, a non-virtual IQ incremental backup together with the Virtual full backup will represent a consistent database. This is because the IQ incremental backup will copy all IQ store data and metadata that have changed during or since the Virtual full backup. Note that even the automatic commit and checkpoint that are part of the backup command modify the IQ store, making an independent system-level backup inconsistent. Trying to use the database without applying the incremental restore will give unpredictable results.

StepsPerforming a decoupled virtual backup

  1. Perform a full IQ backup, using a SQL statement similar to the following:

    BACKUP DATABASE FULL VIRTUAL DECOUPLED
    TO 'iqdemo.full'
    
  2. Perform a system-level backup of the IQ store with a shell command:

    dd if=iqdemo.iq of=iqdemo.iq.copy
    
  3. Perform a non-virtual incremental IQ backup:

    BACKUP DATABASE INCREMENTAL SINCE FULL
    TO 'iqdemo.isf'
    

StepsRestoring from a decoupled virtual backup

  1. Restore the system-level copy of the IQ store, for example:

    dd if =iqdemo.copy of=iqdemo.iq
    
  2. Restore from the IQ full backup file.

    RESTORE DATABASE iqdemo.db FROM 'iqdemo.full'
    
  3. Restore from the IQ incremental backup file.

    RESTORE DATABASE iqdemo.db FROM 'iqdemo.isf'
    
  4. Start the IQ database.