How does LINQ work?

Before we conclude this chapter, we would like to give you a rough idea about how Language Integrated Query (LINQ) works under the hood, in a schematic manner. As we know, LINQ is a declarative language embedded inside a multi-paradigm language. The primary advantage of LINQ is the alignment to the rich type system of C#. Syntactically, LINQ is very similar to SQL language and the evaluation model is very similar to an SQL engine. As an example, let us explore a LINQ query which retrieves information regarding a set of employees by querying Employee and Department table. The query returns an anonymous type consisting of employee name, department name and location of the employee. We are using the comprehension syntax in this particular example:

    var empInfo = from emp in db.Employee
    join dept in db.Department
    on emp.deptid equals dept.nid
    select new
    {
      emp.Name,
      dept.Name,
      emp.Location
    };

While...