Display AM IN, AM OUT, PM IN, PM OUT in a row - sql

Question

I need to return a shift-clock style IN/OUT board from a table of logs.
The expected output is:
ENROLLNO.
DAY
AM_IN
AM_OUT
PM_IN
PM_OUT
1
1
8:36
12:06
1:06
6:36
4
1
7:36
12:06
1:09
7:36
Where:
AM_IN is less than 11:29
AM_OUT is BETWEEN '11:30' AND '12:30'
PM_IN is BETWEEN '12:31' AND '14:00'
PM_OUT is greater than '14:01'
Overall the results should be sorted by ENROLLNO and DAY
So far I have tried this query but it doesn't return the values I need:
ALTER PROCEDURE [dbo].[spViewLOGCSF]
#month nvarchar (max),
#year nvarchar (max)
AS
SELECT
t1.EnrollNo, t1.Day,
MIN(CONVERT(varchar(15), HoursAndMinutes, 100)) AM_IN,
(SELECT MIN(CONVERT(varchar(15), HoursAndMinutes, 100))
FROM tblGLog
WHERE Month = 'April'
AND HoursAndMinutes BETWEEN '11:30' AND '12:30') AM_OUT,
(SELECT MIN(CONVERT(varchar(15), HoursAndMinutes, 100))
FROM tblGLog
WHERE Month = 'April'
AND HoursAndMinutes BETWEEN '12:31' AND '14:00') PM_IN,
MAX(CONVERT(varchar(15), HoursAndMinutes, 100)) PM_OUT
FROM
tblGLog AS t1
LEFT JOIN
tblEnroll AS t2 ON t1.EnrollNo = t2.EnrollNumber
WHERE
t1.Month = #month AND t1.Year = #year
GROUP BY
t1.EnrollNo, t1.Day
The source data table:
Table name: TBLLOGS
Columns are: ENROLLNO, HOURS, DAYS, MONTHS, YEARS , DATETIME
ENROLLNO.
HOURS
DAYS
MONTHS
YEARS
DATETIME
1
8:36
1
APRIL
2021
4/01/2021 8:36:48 AM
1
12:06
1
APRIL
2021
4/01/2021 12:06:48 PM
1
1:06
1
APRIL
2021
4/01/2021 1:06:48 PM
1
5:36
1
APRIL
2021
4/01/2021 5:36:48 PM
1
6:36
1
APRIL
2021
4/01/2021 6:36:48 PM
4
7:36
1
APRIL
2021
4/01/2021 7:36:48 AM
4
12:06
1
APRIL
2021
4/01/2021 12:06:48 PM
4
1:09
1
APRIL
2021
4/01/2021 1:09:48 PM
4
5:32
1
APRIL
2021
4/01/2021 5:36:48 PM
4
7:36
1
APRIL
2021
4/01/2021 7:36:48 PM

Answer 1

Your first issue is that your SP is targeting a different schema to the one you have posted, it is querying tables tblGLog and tblEnroll
For the purposes of this response we will disregard the information provided in the SP script and instead will answer in terms of the posted example data!
You should not use CHAR literals to store your time components, the only columns we need from your example dataset are ENROLLNO and DATETIME, the Day can easily be inferred.
Month and Year can help optimise indexes for some types of execution plans, however your SP is not filtering on Day so you will get more value by storing a DATE typed column for grouping and a TIME typed column for the filtering.
The following solution uses a CTE to transform the dataset, this is not 100% necessary but it illustrates the concrete columns that are required for this type of query. You could optimise your schema by including the additional columns from this CTE into your TBLLOGS schema and setting the values appropriately either as default values, or via triggers or in your INSERT commands.
CROSS APPLY is used to transform the query to apply the specifically requested column expressions, however these columns are not candidates for modifications to the original schema.
NOTE: The time boundary conditions have been closed so that logs at precisely 11:29 and 14:01 are included.
WITH TimePeriodData as
(
SELECT ENROLLNO, [DATETIME], DAYS, HOURS
, CAST([DATETIME] AS Date) AS [Date]
, CAST([DATETIME] AS TIME) AS [TIME]
FROM TBLLOGS
)
SELECT g.ENROLLNO, g.[DATE], g.[DAYS]
, MIN(x.AM_IN) AS AM_IN
, MAX(x.AM_OUT) AS AM_OUT
, MIN(x.PM_IN) AS PM_IN
, MAX(x.PM_OUT) AS PM_OUT
FROM TimePeriodData g
CROSS APPLY (SELECT CASE WHEN [TIME] < '11:30' THEN [HOURS] END AS AM_IN
, CASE WHEN [TIME] BETWEEN '11:30' AND '12:30' THEN [HOURS] END AS AM_OUT
, CASE WHEN [TIME] BETWEEN '12:31' AND '14:00' THEN [HOURS] END AS PM_IN
, CASE WHEN [TIME] > '14:00' THEN [HOURS] END AS PM_OUT
) as x
GROUP BY g.ENROLLNO, g.[Date], g.[DAYS];
See this fiddle: http://sqlfiddle.com/#!18/0073d1/1
Your requirement seems incredibly specific, it would be simpler logic to specify the midday break time as 12:30, then we only have a single conversion per-row. If this value is a constant then it is a candidate for inclusion in the data schema.
This next query deliberately DOES NOT format the output for the DAYS and HOURS columns as requested, instead the SQL query returns the exact data type so that you can easily extend this query to other situations. Formatting the specific output should be handled in the representation layer
WITH TimePeriodData as
(
SELECT ENROLLNO, [DATETIME], DAYS, HOURS
, CAST([DATETIME] AS Date) AS [Date]
, CAST([DATETIME] AS TIME) AS [TIME]
, CASE WHEN DATEPART(hour, [DATETIME]) >=14 THEN 1 ELSE 0 END AS [IS_PM]
FROM TBLLOGS
)
SELECT g.ENROLLNO, g.[DATE]
, MIN(x.AM) AS AM_IN
, MAX(x.AM) AS AM_OUT
, MIN(x.PM) AS PM_IN
, MAX(x.PM) AS PM_OUT
FROM TimePeriodData g
CROSS APPLY (SELECT CASE WHEN [IS_PM] = 0 THEN [TIME] END AS AM
, CASE WHEN [IS_PM] = 1 THEN [TIME] END AS PM
) as x
GROUP BY g.ENROLLNO, g.[Date], g.[DAYS];
This will return: http://sqlfiddle.com/#!18/0073d1/10
ENROLLNO
DATE
AM_IN
AM_OUT
PM_IN
PM_OUT
1
2021-04-01
08:36:48
12:06:48
13:06:48
18:36:48
4
2021-04-01
07:36:48
12:06:48
13:09:48
19:36:48
The following fiddle http://sqlfiddle.com/#!18/b09ee3/2 demonstrates how the query could be simplfied:
SELECT g.ENROLLNO, g.[DATE]
, MIN(x.AM) AS AM_IN
, MAX(x.AM) AS AM_OUT
, MIN(x.PM) AS PM_IN
, MAX(x.PM) AS PM_OUT
FROM TBLLOGS g
CROSS APPLY (SELECT CASE WHEN [IS_PM] = 0 THEN [TIME] END AS AM
, CASE WHEN [IS_PM] = 1 THEN [TIME] END AS PM
) as x
GROUP BY g.ENROLLNO, g.[Date];
There is no example here of how to apply this to the original SP because the exact table schema is not provided, no explanation for the un-used LEFT JOIN reference in that SP and the Hardcoded 'April' filtering ignored the input parameters... there is just too much mess there that I choose not to be involved with ;)