How can I convert SQL to LINQ-to-SQL - sql

Question

SELECT Cities.CityName, Customers.CustomerName, SUM(Bills.Sarees)
FROM Bills INNER JOIN
Customers ON Bills.CustomerID = Customers.CustomerID INNER JOIN
Cities ON Customers.CityID = Cities.CityID
Group by CustomerName, CityName
I have tried to make it as below.... but I am unable to insert group by clause within
var query = db.Bills.Join(db.Customers, c => c.CustomerID, p => p.CustomerID, (c, p) => new
{
c.Customer.CustomerID,
c.Customer.CustomerName,
c.Customer.City.CityName,
c.Customer.Mobile1,
c.Customer.Mobile2,
c.Customer.Telephone,
c.Customer.Email,
c.Sarees
});

Answer 1

Looking at your SQL, you need something like this I guess:
var query = db.Bills
.Join(db.Customers, b => b.CustomerID, c => c.CustomerID, (b, c) => new
{
b.Sarees,
c.CustomerName,
c.CityID
})
.Join(db.Cities, j => j.CityID, c => c.CityID, (j, c) => new
{
j.Sarees,
j.CustomerName,
j.CityID,
c.CityName
})
.GroupBy(o => new { o.CustomerName, o.CityName })
.Select(o => new { o.Key.CityName, o.Key.CustomerName, Sum = o.Sum(i => i.Sarees) });