Split a coma separated string in a particular format - sql

Question

I have a table with a column which represent hierarchy path, so when i execute the SQL query
select hierachypath from mytable where id=10
for a particular row i will get the result like this
hieracheypath
--------------
1,2,3,4,5,6,7,8,9,10
select hierachypath from mytable where id=10
I want to get a result like
1,2,3,4,5,6,7,8,9,10
1,1,2,3,4,5,6,7,8,9
1,2,3,4,5,6,7,8
1,2,3,4,5,6,7
1,2,3,4,5,6
1,2,3,4,5
1,2,3,4
1,2,3
1,2
1
OR
1
1,2
1,2,3
1,2,3,4
1,2,3,4,5
1,2,3,4,5,6
1,2,3,4,5,6,7
1,2,3,4,5,6,7,8
1,2,3,4,5,6,7,8,9
1,2,3,4,5,6,7,8,9,10
I had try this way
Declare #heiracheypath nvarchar(4000) ='1,2,3,4,5,6,7,8,9,10'
declare #Result TABLE (Column1 VARCHAR(100))
Declare #tcount int
SELECT #tcount=(len(#heiracheypath) - LEN(REPLACE(#heiracheypath,',','')) + 1)
DECLARE #IntLocation INT
WHILE (CHARINDEX(',', #heiracheypath, 0) > 0)
BEGIN
SET #IntLocation = CHARINDEX(',', #heiracheypath, 0)
INSERT INTO #Result (Column1)
--LTRIM and RTRIM to ensure blank spaces are removed
SELECT RTRIM(LTRIM(SUBSTRING(#heiracheypath, 0, #IntLocation)))
SET #heiracheypath = STUFF(#heiracheypath, 1, #IntLocation, '')
END
INSERT INTO #Result (Column1)
SELECT RTRIM(LTRIM(#heiracheypath))--LTRIM and RTRIM to ensure blank spaces are removed
select * from #Result
but the result was
Column1
-------
1
2
3
4
5
6
7
8
9
10

Answer 1

The code in the question Looks like T-SQL - so here's a simple solution without common table expressions:
DECLARE #heiracheypath nvarchar(4000) ='1,2,3,4,5,6,7,8,9,10';
SELECT SUBSTRING(#heiracheypath, 1, ci-1) As Paths
FROM
(
SELECT CHARINDEX(',',#heiracheypath, N) As ci
FROM
(
SELECT TOP(LEN(#heiracheypath)) ROW_NUMBER() OVER(ORDER BY ##SPID) As N
FROM sys.objects A
) AS Tally
UNION
SELECT LEN(#heiracheypath) + 1
) As CommaIndexes
WHERE ci > 0
ORDER BY ci
The Tally derived table contains numbers from 1 to the length of the value,
the CommaIndexes table contains the distinct indexes of each comma in the value,
the union part is to also return the full string,
and the outer most select statement simply use substring to return the relevant parts of the string.
This could be simplified further by combining the tally derived table with the commaIndexs derived table:
SELECT SUBSTRING(#heiracheypath, 1, ci-1) As Paths
FROM
(
SELECT TOP(LEN(#heiracheypath)) CHARINDEX(',',#heiracheypath, ROW_NUMBER() OVER(ORDER BY ##SPID)) As ci
FROM sys.objects A
UNION SELECT LEN(#heiracheypath) + 1
) As CommaIndexes
WHERE ci > 0
ORDER BY ci
Result:
Paths
1
1,2
1,2,3
1,2,3,4
1,2,3,4,5
1,2,3,4,5,6
1,2,3,4,5,6,7
1,2,3,4,5,6,7,8
1,2,3,4,5,6,7,8,9
1,2,3,4,5,6,7,8,9,10