title: Dealing with circular reference when entering data in SQL
body: <p>What kind of sql tricks you use to enter data into two tables with a circular reference in between. </p>
  
  <pre><code>Employees
      EmployeeID &lt;PK&gt;
      DepartmentID &lt;FK&gt; NOT NULL
  
  Departments
      DepartmentID &lt;PK&gt;
      EmployeeID &lt;FK&gt; NOT NULL
  </code></pre>
  
  <p>The employee belongs to a department, a department has to have a manager (department head).</p>
  
  <p>Do I have to disable constraints for the insert to happen?</p>