T-SQL Split Word into characters - string

Question

I have searched everywhere and I cannot find this implementation anywhere.
Let's say I have the word: QWERTY
I want to obtain this table:
Q
W
E
R
T
Y
Or for QWERTY AnotherWord I want to obtain
Q
W
E
R
T
Y
[space character here]
A
n
o
t
h
e
r
W
o
r
d

Answer 1

Do it like this:
select substring(a.b, v.number+1, 1)
from (select 'QWERTY AnotherWord' b) a
join master..spt_values v on v.number < len(a.b)
where v.type = 'P'

Answer 2

Declare #word nvarchar(max)
Select #word = 'Hello This is the test';
with cte (Number)as
(Select 1
union all
select Number +1 From cte where number <len(#word)
)
select * from Cte Cross apply (Select SUBSTRING(#word,number,1 ) ) as J(Letter)

Answer 3

Here you have it:
create table #words (
character varchar(1)
)
declare #test varchar(10)
select #test = 'QWERTY'
declare #count int, #total int
select #total = len(#test), #count = 0
while #count <= #total
begin
insert into #words select substring(#test, #count, 1)
select #count = #count + 1
end
select * from #words
drop table #words

Answer 4

Here is a table-valued function (derived from aF's temp table implementation). It differs slightly from aF's implementation in that it starts with #count=1; this excludes an extraneous leading space.
CREATE FUNCTION [dbo].[Chars] (#string VARCHAR(max))
RETURNS #chars TABLE (character CHAR)
AS
BEGIN
DECLARE #count INT,
#total INT
SELECT #total = Len(#string),
#count = 1
WHILE #count <= #total
BEGIN
INSERT INTO #chars
SELECT Substring(#string, #count, 1)
SELECT #count = #count + 1
END
RETURN
END
Usage:
SELECT * FROM dbo.chars('QWERTY AnotherWord')

Answer 5

Please, PLEASE avoid referencing systems tables, specifically system tables in system databases. In fact, the selected answer above probably won't compile in a Visual Studio 2013 Database Project
Table variables are fine, but recursion with a CTE is the answer:
DECLARE #str VARCHAR(max)
SET #str = 'QWERTY AnotherWord'
WITH Split(stpos,endpos)
AS(
SELECT 1 AS stpos, 2 AS endpos
UNION ALL
SELECT endpos, endpos+1
FROM Split
WHERE endpos <= LEN(#str)
)
SELECT
'character' = SUBSTRING(#str,stpos,COALESCE(NULLIF(endpos,0),LEN(#str)+1)-stpos)
,'charindex' = stpos
FROM Split
That said, the use for the code above is to get a table full of letters representing different permissions for a user. That is not the way to do this. Make a table with an ID, a permission code and a description then make a linking table between the users table and the new permissions table. this gives you the same abilities and doesn't make you solve dumb problems like this.

Answer 6

I wanted to contribute my own solution to this problem.
Convert into table valued function as desired (and handle nulls however you wish)
DECLARE #str nvarchar(100) = 'QWERTY AnotherWord'
DECLARE #len int = LEN(#str)-1;
--create a string of len(#str)-1 commas
--because STRING_SPLIT will return n rows for n-1 commas
--split string to return a table of len(#str) rows
--provide an index column named [index]
WITH [rows] AS (
SELECT
ROW_NUMBER() OVER (ORDER BY [value]) [index]
FROM STRING_SPLIT(REPLICATE(',', #len), ',')
),
--for each row, take the index number
--and extract the character from that index
[split] AS (
SELECT
[index],
SUBSTRING(#str,[index],1) [char]
FROM [rows]
)
--maintain the same order
--and return just the extracted characters
SELECT
--[index],
[char]
FROM [split]
ORDER BY [index] ASC
output:
char
----
Q
W
E
R
T
Y
A
n
o
t
h
e
r
W
o
r
d

Answer 7

I like the use of REPLICATE() and substring in the answer by #drrollergator. I find value in the answer below, in accounting for:
The truncation to 8000 characters mentioned by Microsoft learn/docs. Explicitly casting to a larger datatype will avoid this.
the unordered ROW_NUMBER as mentioned in [https://stackoverflow.com/questions/44105691/row-number-without-order-by].
Sample SQL:
DECLARE #str NVARCHAR(MAX) = N'QWERTY AnotherWord'
SELECT
ss.[value]
FROM
( SELECT TOP(LEN(#str))
SUBSTRING(#str,n.[i],1) [value]
,n.[i]
FROM ( SELECT ROW_NUMBER() OVER(ORDER BY (SELECT '.')) [i] FROM STRING_SPLIT(REPLICATE(CAST('.' AS VARCHAR(MAX)),LEN(#str) - 1),'.') ) n([i])
/* [A.] Generate numbers equal to character count in #expression */
ORDER BY n.[i]
/* [B.] Return 1-Char-Substring for each number/position */
) ss