Interview › Databases & Caching
What is the difference between automated backups and manual snapshots in RDS?
Databases & Caching · Basic level
Answer
Automated backups are retained for a configured window and support point-in-time recovery. Manual snapshots are retained until deleted and are useful before risky changes or for long-term copies. PITR restores from a base backup plus transaction logs to create a new database at a chosen timestamp.
Technical explanation
PITR does not rewind the existing DB in place; it restores a new instance that must be validated and cut over or used for data repair.
Retention should be based on business recovery needs and detection time for corruption, not just default cost settings.
Restore testing is part of the backup strategy because backup success does not prove recovery success.
Hands-on example
PITR example:
$ aws rds restore-db-instance-to-point-in-time --source-db-instance-identifier orders-prod --target-db-instance-identifier orders-pitr-20260630 --restore-time 2026-06-30T10:14:30Z
Then compare row counts, extract repaired rows if needed, run smoke tests, and decide between partial repair and full cutover.
Check how well your resume matches the role with our free resume checker— match score, ATS check, and the skills you're missing.
More Databases & Caching interview questions
- What is Amazon RDS, and what does it manage for you versus self-managed databases?
- What database engines does RDS support?
- What is the difference between RDS and Aurora?
- What is Multi-AZ in RDS, and how does automatic failover work?
- How long does an RDS Multi-AZ failover typically take, and what triggers it?
- What is the difference between Multi-AZ and a read replica?
- When would you use a read replica, and can it become a standalone database?
- Can a read replica be in a different region, and why would you do that?