Have you ever lost data or caused an outage with a database change? What happened?

Note: Do not answer "never". Everyone who has worked at scale has a story, and claiming otherwise reads as inexperience or dishonesty. Pick a real incident with a clean recovery.

A good answer has four beats:

• The mistake, stated plainly. An UPDATE without a WHERE clause, a migration that locked a large table during peak traffic, a DROP on the wrong environment.
• How fast you owned it. Interviewers care much more about whether you told someone immediately than about the mistake itself.
• The recovery. Point-in-time recovery from binary logs, a restore into a scratch schema and a targeted re-insert, or a failover to a replica.
• The guardrail you added. Running in a transaction so you can ROLLBACK, enabling sql_safe_updates, requiring a peer to review every migration, or removing write access to production entirely.

The last beat is what actually gets you hired.