How to do grouping, aggregation (Sum, Count, Max, Min) via LINQ?
var groupedData = context.Orders
.GroupBy(o => o.CustomerId)
.Select(g => new
CustomerId = g.Key,
TotalOrders = g.Count(),
TotalAmount = g.Sum(o => o.Amount),
MaxAmount = g.Max(o => o.Amount),
MinAmount = g.Min(o => o.Amount)
});