What happens when you access a navigation property on a detached entity?

Short answer: Throws InvalidOperationException or returns null since no tracking or lazy loading. Need to attach entity or explicitly load navigation properties.

Example code

Throws InvalidOperationException or returns null since no tracking or lazy loading. Need to attach entity or explicitly load navigation properties.

Real-world example (ShopNest)

ShopNest’s order service uses EF Core to save an Order and its line items in one SaveChangesAsync() call inside a transaction.

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.