title: Why is there no SingleOrDefaultAsync for IQueryables?
body: <p>The following code does not compile because SingleOrDefaultAsync() is not a suitable extension for GetAppointments(). I was just wondering why ...</p>
  
  <pre><code>public IQueryable&lt;Appointment&gt; GetAppointments()
  {
          return Context.Appointments;
  }
  
  public async Task&lt;Appointment&gt; GetAppointmentAsync(int appointmentId)
  {
          return await GetAppointments().SingleOrDefaultAsync(a =&gt; a.ID == appointmentId);
  }
  </code></pre>
  
  <p>I am using EF 6.0.0. And please ignore what I am doing here exactly. I just tried to make things easier than they actually are in my project.</p>