Query to print Which Shift based on the time

Question

Need to sort and sum data based on the shifts in our department....
First shift runs from 4:50 am to 2:45 pm, second shift runs from 3:00 pm to 1:00 am and any time in between is the break time.
I cannot get the data to print first shift , break time and second shift correctly
Sample Data :
DROP TABLE TIME_SHIFT CASCADE CONSTRAINTS;
-- TIME_SHIFT (Table)
CREATE TABLE TIME_SHIFT ( TRX_DATE DATE ) ;
Insert into TIME_SHIFT (TRX_DATE) Values (TO_DATE('10/03/2011 10:30:23', 'MM/DD/YYYY HH24:MI:SS'));
Insert into TIME_SHIFT (TRX_DATE) Values (TO_DATE('12/30/2011 11:40:02', 'MM/DD/YYYY HH24:MI:SS'));
Insert into TIME_SHIFT (TRX_DATE) Values (TO_DATE('12/30/2011 23:55:10', 'MM/DD/YYYY HH24:MI:SS'));
Insert into TIME_SHIFT (TRX_DATE) Values (TO_DATE('12/30/2011 16:54:15', 'MM/DD/YYYY HH24:MI:SS'));
Insert into TIME_SHIFT (TRX_DATE) Values (TO_DATE('10/03/2011 10:26:10', 'MM/DD/YYYY HH24:MI:SS'));
Insert into TIME_SHIFT (TRX_DATE) Values (TO_DATE('10/04/2011 00:30:08', 'MM/DD/YYYY HH24:MI:SS'));
Insert into TIME_SHIFT (TRX_DATE) Values (TO_DATE('10/04/2011 02:47:08', 'MM/DD/YYYY HH24:MI:SS'));
Insert into TIME_SHIFT (TRX_DATE) Values (TO_DATE('10/12/2011 15:30:08', 'MM/DD/YYYY HH24:MI:SS'));
Insert into TIME_SHIFT (TRX_DATE) Values (TO_DATE('10/04/2011 00:00:00', 'MM/DD/YYYY HH24:MI:SS'));
Insert into TIME_SHIFT (TRX_DATE) Values (TO_DATE('10/04/2011 12:00:00', 'MM/DD/YYYY HH24:MI:SS'));
Insert into TIME_SHIFT (TRX_DATE) Values (TO_DATE('11/22/2011 03:00:00', 'MM/DD/YYYY HH24:MI:SS'));
COMMIT;
SELECT TO_CHAR (trx_date, 'MM/DD/YYYY') ,TO_CHAR (trx_date, 'HH:MI:SSAM')
-- (case
-- when TO_CHAR(trx_date,'HH24:MI:SS') between '04:50:00' and '14:45:00'
-- then 'FIRST SHIFT'
-- when TO_CHAR(trx_date,'HH24:MI:SS') between '15:00:00' and '01:00:00'
-- then 'SECOND SHIFT'
-- else 'BREAK TIME'
-- end
-- ) WHICH_SHIFT
FROM TIME_SHIFT ;
Expected result :
10/03/2011        10:30:23AM     FirstShift
12/30/2011        11:40:02AM     FirstShift
12/30/2011        11:55:10PM     SecondShift
12/30/2011        04:54:15PM     SecondShift
10/03/2011        10:26:10AM     FirstShift
10/04/2011        12:30:08AM     FirstShift
10/04/2011        02:47:08AM     BreakTime
10/12/2011        03:30:08PM     SecondShift
10/04/2011        12:00:00AM     SecondShift
10/04/2011        12:00:00PM     FirstShift
11/22/2011        03:00:00AM             BreakTimeThanks for the help in advance.

Answer 1

Hi,
In everyday speech, when we hear "Between 3:00 PM and 1:00 AM", we understand that it means one range of 10 consecutive hours. That's not how the SQL BETWEEN operator works, however. "x BETWEEN y AND z" in SQL is exactly equivalent to "x >= y AND x <= z". If y < z, it never be TRUE.
Here's one way to do what you want:
SELECT     TO_CHAR (trx_date, 'MM/DD/YYYY')
,     TO_CHAR (trx_date, 'HH:MI:SSAM')
,     CASE
         WHEN  TO_CHAR (trx_date, 'HH24:MI:SS') BETWEEN '04:50:00'
                                              AND         '14:45:00'
         THEN  'FIRST SHIFT'
         WHEN  TO_CHAR (trx_date, 'HH24:MI:SS') BETWEEN '01:00:01'
                                              AND         '14:59:59'
         THEN  'BREAK TIME'
         ELSE  'SECOND SHIFT'
     END               AS which_SHIFT
FROM      time_shift
; This is close to what you tried, which was
(1) see if it's First Shift
(2) if not (1), see if it's Second Shift
(3) if not (1) or (2), it must be Break time
The problem with that is that, as far as SQL is concerned, going just by HH24:MI:SS, the Second shiift is two disjoint periods, and you have to test for each one separately. The query above reverses the last two tests:
(1) see if it's First Shift
(2) if not (1), see if it's Break Time
(3) if not (1) or (2), it must be Second Shift
It would be a little more coding, but perhaps clearer, to do it this way
,     CASE
         WHEN  TO_CHAR (trx_date, 'HH24:MI:SS') BETWEEN '04:50:00'
                                              AND         '14:45:00'
         THEN  'FIRST SHIFT'
         WHEN  TO_CHAR (trx_date, 'HH24:MI:SS') BETWEEN '15:00:00'
                                              AND         '24:00:00' -- or '23:59:59', if you prefer
           OR  TO_CHAR (trx_date, 'HH24:MI:SS') BETWEEN '00:00:00'
                                              AND         '01:00:00
         THEN  'SECOND SHIFT'
         ELSE  'BREAK TIME'
     END               AS which_SHIFT I wish we could mark questions as "Correct" or "Helpful". You provided a good set of sample data in a useable form (you even included DROP TABLE and COMMIT statements), you gave a clear explanation of the problem with the desirred results, and you showed what you had already tried. Lots of people who have used this forum for years haven't learned to do that yet. Keep up the good work!
Don't forget to mention which version of Oracle you're using. In this example, it may not matter. (The query above will work in Oracle 8.1 or higher.) But it never hursts o say something like "I'm using Oracle 10.2.0.3.0".
Edited by: Frank Kulash on Dec 1, 2011 12:23 PM