Multiple CSV Column to Row SQL Query - sql

Question

I have following data
I want to Convert Column to Row
I have use following Query ::
Select Distinct [ApplicantID],
Split.a.value('.', 'VARCHAR(100)') AS Subjects,
hoursperweek,[Days],[Time]
From ( Select
Cast ('<M>' + REPLACE([Subjects], ',', '</M><M>') + '</M>' AS XML)
AS Subjects , ApplicantID, hoursperweek,[Days],[Time]
From [dbo].[Progrm])
AS A CROSS APPLY Subjects.nodes ('/M') AS Split(a)
It give me following Result
but I want to seprate Subjects, Hoursperweek, days, time. How can I do that ?
ApplicantID Subjects HoursPerWeek Days Time
1 a 12 Sun 12:45:12
1 b 25 Mon 14:45:12

Answer 1

Here is a function to split the Comma separated values into Rows
CREATE FUNCTION dbo.Splitstrings (#List NVARCHAR(MAX),
#Delimiter NVARCHAR(255))
RETURNS #split_tab TABLE (
RN INT IDENTITY(1, 1),
SPLIT_VAL VARCHAR(100))
WITH SCHEMABINDING
AS
BEGIN ;
;WITH E1(N)
AS (SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1),
E2(N) AS (SELECT 1 FROM E1 a,E1 b),
E4(N) AS (SELECT 1 FROM E2 a, E2 b),
E42(N) AS (SELECT 1 FROM E4 a, E2 b),
cteTally(N)
AS (SELECT 0
UNION ALL
SELECT TOP (Datalength(Isnull(#List, 1))) Row_number()OVER (
ORDER BY (SELECT NULL))
FROM E42),
cteStart(N1)
AS (SELECT t.N + 1
FROM cteTally t
WHERE ( Substring(#List, t.N, 1) = #Delimiter
OR t.N = 0 ))
INSERT INTO #split_tab
SELECT SPLIT_VAL= Substring(#LIST, S.N1, Isnull(NULLIF(Charindex(#DELIMITER, #LIST, S.N1), 0) - S.N1, 8000))
FROM CTESTART S;
RETURN
END
Now the ugly code to split the data
;WITH data
AS (SELECT 1 ApplicantID,
'a,b' Subjects,
'12,25' HoursPerWeek,
'sun,mon' Days,
'12:45:12,14:45:12' Time),
sub
AS (SELECT RN,
ApplicantID,
Subjects=SPLIT_VAL
FROM data
CROSS apply Splitstrings (Subjects, ',')),
HPW
AS (SELECT RN,
ApplicantID,
HoursPerWeek=SPLIT_VAL
FROM data
CROSS apply Splitstrings (HoursPerWeek, ',')),
Days
AS (SELECT RN,
ApplicantID,
Days=SPLIT_VAL
FROM data
CROSS apply Splitstrings (Days, ',')),
Time
AS (SELECT RN,
ApplicantID,
Time=SPLIT_VAL
FROM data
CROSS apply Splitstrings (Time, ','))
SELECT D.APPLICANTID,
S.SUBJECTS,
H.HOURSPERWEEK,
DA.DAYS,
T.TIME
FROM DATA D
FULL OUTER JOIN SUB S
ON D.APPLICANTID = S.APPLICANTID
FULL OUTER JOIN HPW H
ON D.APPLICANTID = H.APPLICANTID
AND H.RN = S.RN
FULL OUTER JOIN DAYS DA
ON D.APPLICANTID = DA.APPLICANTID
AND DA.RN = COALESCE(S.RN, H.RN)
FULL OUTER JOIN TIME T
ON D.APPLICANTID = T.APPLICANTID
AND T.RN = COALESCE(S.RN, H.RN, DA.RN)
Result:
╔═════════════╦══════════╦══════════════╦══════╦══════════╗
║ APPLICANTID ║ SUBJECTS ║ HOURSPERWEEK ║ DAYS ║ TIME ║
╠═════════════╬══════════╬══════════════╬══════╬══════════╣
║ 1 ║ a ║ 12 ║ sun ║ 12:45:12 ║
║ 1 ║ b ║ 25 ║ mon ║ 14:45:12 ║
╚═════════════╩══════════╩══════════════╩══════╩══════════╝
This is the reason we should never store comma separated values into single column. When you want to parse the data things get difficult and we need to such ugly codes to parse the data