title: Displaying only free time slots which haven't been booked for any date
body: <p>The following query displays all free time slots for a specific which haven't been booked:-</p>
  
  <pre><code> SELECT DISTINCT tbl_available.timeslot
  FROM            tbl_appointment RIGHT JOIN
                       tbl_available ON (tbl_appointment.employeeID = tbl_available.employeeID) AND (tbl_appointment.apptTime = tbl_available.timeslot)
  WHERE        tbl_appointment.apptTime IS NULL
  ORDER BY 1;
  </code></pre>
  
  <p>This is fine but I'm trying to get it so that it runs this query based on any date which is passed in as a parameter using c#. (I only need help with the SQL side of things)</p>
  
  <p>Using the following tables:-</p>
  
  <pre><code> Appointment:-      Availability:-
   apptTime           timeSlot
   apptDate           DoctorId
   patientID
  </code></pre>
  
  <p>Any suggestions would be greatly appreciated.</p>