How do you test database interactions in integration tests?

Short answer: You use a test database or in-memory database to run queries and verify data persistence and retrieval, ensuring the data layer works as expected without affecting production data.

Real-world example (ShopNest)

Arrange a cart with 2 items → Act Checkout() → Assert total and that payment was called once.

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.