FULL OUTER JOIN: Returns all rows from both tables, with matching rows where?

Short answer: available. If there’s no match, NULL is returned for the missing side. Use case: When you want all records from both tables.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.