A company is planning an online backup strategy for a highly available database application. Which key component must be included in the backup strategy?

Rollback logs (undo logs) are used internally by the database engine to reverse uncommitted transactions in flight and are not a recoverable artifact used in backup and restore operations.

Temp logs hold transient data for in-progress queries and temporary objects and are automatically discarded when sessions end, making them irrelevant to backup strategy.

Transaction logs capture every committed database operation and are essential for online backups because the database continues to process writes during the backup window, creating a moving target. They allow the database engine to roll the backup forward to a transactionally consistent point in time after the backup completes, which is the standard recovery mechanism for highly available databases that cannot be taken offline. Without transaction log backups included in the strategy, the resulting backup image would be crash-consistent at best and potentially unrestorable.

Event logs record application and system operational events at the OS or platform level and contain no database transaction data needed for backup consistency or recovery.