title: Update one DataTable from another
body: <pre><code>create table employee
  (
      id int,
      name varchar(10),
      dept_id int,
      dept_name varchar(10)
  );
  
  insert into employee values(1, 'ABC1', 1, '');
  insert into employee values(2, 'ABC2', 2, '');
  insert into employee values(3, 'ABC3', 1, '');
  insert into employee values(4, 'ABC4', 2, '');
  insert into employee values(5, 'ABC5', 1, '');
  
  create table dept
  (
      dept_id int,
      dept_name varchar(10)
  );
  
  insert into dept values(1, 'XYZ1');
  insert into dept values(2, 'XYZ2');
  </code></pre>
  
  <pre><b>UPDATE e
  SET    e.dept_name = d.dept_name
  FROM   employee AS e
         JOIN dept AS d
         ON e.dept_id = d.dept_id</b></pre>
  
  <p>How do I convert above query (in bold letters) to a LINQ query?</p>