How to perform a left outer join in LINQ?

Short answer: How to perform a left outer join in LINQ? var leftJoin = from d in departments join e in employees on d.Name equals e.Department into empGroup from emp in empGroup.DefaultIfEmpty() select new { Department = d.Name, EmployeeName = emp?.Name ??

Real-world example (ShopNest)

A sales report joins orders and customers, then GroupBy(c => c.City) to show revenue per city.

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.