Query from multiple “Not In” queries without using UNION

Question

Hard to make good title for exactly what I need.

This revolves around 3 tables, and is an appointment booking system, and I need to get a list of each doctor/nurse and the time slots they're free.

I don't want to use UNION as with the first sql below it means I have to declare the names of each doctor, which I don't want to do.

Tables...

UserDetails:

ID    Role   Surname   Clinic
1    Doctor   House      1
2    Doctor   Bob        1
3    Nurse    Smith      1
4    Doctor   Jim        2
5    Nurse    Grant      2 
6    Patient  Billy      1
7    Patient  Jones      1

TimeSlots:

ID   TimeSlot
1     10:00
2     10:30
3     11:00
4     11:30
11    16:30
12    17:00

Appointments:

ID  StaffID   PatientID  TimeSlot   AppDate
1      1         6          1        today   
2      1         7          3        today
3      2         6          2        today
4      1         6          4       tomorrow

(StaffID and PatientID, are Foreign Keys ID from Users Table) I need a query which outputs each time slot and the Doc/Nurse for when they haven't got an appointment for today (or any day based on "AppDate")

I can do this for a specific doctor/nurse:

SELECT TimeSlots.TimeSlot, Users.Role, Users.Surname, Users.Clinic 
FROM TimeSlots, Users 
WHERE 
    TimeSlots.ID NOT IN 
        (SELECT Appointments.TimeSlot
        FROM Appointments  
            INNER JOIN Users    
            ON Appointments.MedicalStaffID = Users.ID 
        WHERE AppDate = CONVERT(DATE,GETDATE()) AND Users.Surname = 'House')
AND
    Users.Surname = 'House'
ORDER BY TimeSlots.TimeSlot;

Which gives me:

TimeSlot   Role   Surname    Clinic
  10:30   Doctor   House       1
  11:30   Doctor   House       1
  16:30   Doctor   House       1
  17:00   Doctor   House       1

Which is fine, but I need 1 query to display this for all doctors/nurses, so I have:

   TimeSlot   Role   Surname    Clinic
     10:30   Doctor   House       1
     11:30   Doctor   House       1
     16:30   Doctor   House       1
     17:00   Doctor   House       1
     10:00   Doctor   Bob         1
     11:00   Doctor   Bob         1
     11:30   Doctor   Bob         1
     16:30   Doctor   Bob         1
     17:00   Doctor   Bob         1

and so it can also be ordered by the time.

I initially tried working with:

SELECT TimeSlots.TimeSlot, Users.Role, Users.Surname, Users.Clinic 
FROM TimeSlots, Users 
WHERE 
    TimeSlots.ID NOT IN (SELECT TimeSlot FROM Appointments  WHERE AppDate = GETDATE() AND (Users.Clinic = 'Werrington') AND (Users.Role = 'Doctor' OR Users.Role = 'Nurse'))
AND
    (Users.Role = 'Doctor' OR Users.Role = 'Nurse')
AND
    (Users.Clinic = 'Werrington')
ORDER BY TimeSlots.TimeSlot;

But that just outputs every Doctor with every Timeslot

On a side note I feel theres a better way to structure the look of the resulting table, can't think of how.

Answer 1

If I understood the question correctly, this should give you what you're loking for...

SET NOCOUNT ON;

DECLARE @UserDetails TABLE (
    ID      int,
    Role    varchar(50),
    Surname varchar(50),
    Clinic  int )

INSERT @UserDetails VALUES (1, 'Doctor', 'House', 1)
INSERT @UserDetails VALUES (2, 'Doctor', 'Bob', 1)
INSERT @UserDetails VALUES (3, 'Nurse', 'Smith', 1)
INSERT @UserDetails VALUES (4, 'Doctor', 'Jim', 2)
INSERT @UserDetails VALUES (5, 'Nurse', 'Grant', 2 )
INSERT @UserDetails VALUES (6, 'Patient', 'Billy', 1)
INSERT @UserDetails VALUES (7, 'Patient', 'Jones', 1)

DECLARE @TimeSlots TABLE (
    ID          int,
    TimeSlot    varchar(50) )

INSERT @TimeSlots VALUES (1 , '10:00' )
INSERT @TimeSlots VALUES (2 , '10:30' )
INSERT @TimeSlots VALUES (3 , '11:00' )
INSERT @TimeSlots VALUES (4 , '11:30' )
INSERT @TimeSlots VALUES (11, '16:30' )
INSERT @TimeSlots VALUES (12, '17:00' )

DECLARE @Appointments TABLE (
    ID          int,
    StaffID     int,
    PatientID   int,
    TimeSlotID  int,
    AppDate     varchar(50) )

INSERT @Appointments VALUES (1, 1, 6, 1, 'today' ) 
INSERT @Appointments VALUES (2, 1, 7, 3, 'today' )
INSERT @Appointments VALUES (3, 2, 6, 2, 'today' )
INSERT @Appointments VALUES (4, 1, 6, 4, 'tomorrow' )

SET NOCOUNT OFF;

WITH CompleteSchedule AS (
    SELECT      UD.ID as UserID, UD.Role, UD.Surname, UD.Clinic, TS.ID as TimeSlotID, TS.TimeSlot
    FROM        @UserDetails UD
    CROSS JOIN  @TimeSlots TS
)
SELECT      CS.*
FROM        CompleteSchedule CS
LEFT JOIN   @Appointments A ON A.StaffID = CS.UserID AND A.TimeSlotID = CS.TimeSlotID AND A.AppDate = 'today'
WHERE       A.ID is null
ORDER BY    CS.UserID, CS.TimeSlotID

The CTE will generate a "table" of every staff member X every timeslot. Then you Left Join that with your appoints for the given day. Any resulting row that does not have an appointment ID is an open timeslot.