LINQ vs IQueryable?

Short answer: LINQ vs IQueryable What interviewers test Deferred execution DB performance LINQ (IEnumerable) var data = users.Where(x => x.Age > 30).ToList(); Executes in memory IQueryable var data = db.Users.Where(x => x.Age > 30); Translates to SQL Executes in DB Interview line “IQueryable builds expressions; IEnumerable executes them.” 🔟 Write clean, production-ready C# code What interviewers test Professional maturity…

Explain a bit more

Principles Small methods Clear naming No magic values Proper exceptions public class OrderService

Example code

{
public void PlaceOrder(Order order)
{
if (order == null) throw new ArgumentNullException(nameof(order)); Validate(order); Save(order); }
private void Validate(Order order)
{
if (order.Total <= 0) throw new InvalidOperationException("Invalid total"); }
private void Save(Order order)
{ // persistence logic }
}

Real-world example (ShopNest)

MNC rounds expect working code plus explanation. Walk through an example input from a ShopNest cart list, then discuss time and space.

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.