BACKUP backs up committed data only.
Backups begin with a commit and an automatic checkpoint. At this point, the backup program determines what data will be backed up. It backs up the current snapshot version of your database as of the time of this checkpoint. Any data that is not yet committed when this checkpoint occurs is not included in the backup.
A second automatic checkpoint occurs at the end of backup. Any data that is committed while the backup is in progress is included in any subsequent backups.
SAP Sybase IQ backs up only those recoverable database blocks actually in use at the time of backup. Free blocks are not backed up.
SAP Sybase IQ backs up the database files and the catalog information that pertains to the SAP Sybase IQ database to which you are connected. It does not back up the transaction log file. It does not use the transaction log to restore the database.
If for any reason all the commands in the transaction do not process properly, or your database is missing files, the backup fails.