Error when converting data to XML in SQL Server - sql

Question

I need to retrieve the content in position 10 of a comma separated string in a View table.
Row 1 N,l,S,T,A,,<all>,,N,A,N,N,N,Y,Y,,Y,Y,Y,,AA,SA,Enterprise,
Row 2 M,,A,S,AS,SS,AS,N,N,N,N,Y,Y,Y,ENTERPRISE,S,,A
Row 3 L,,A,D,S,A,A,AA,Y,Y,Y,YNN,N,N,N,N,A,AA,AD,D,D
Div1 is the name of my column, Div2 is the name of the result column. I use the following code:
SELECT TOP (2000)
[Id],
CONVERT(XML,'<x>' + REPLACE(REPLACE(REPLACE(Div1, '>', ''), '<', ''), ',', '</x <x>') + '</x>').value('/x[10]', 'VARCHAR(MAX)') [Div2],
Div1
FROM
[dbo].[database]
I use character type VARCHAR(MAX) because that is the type for Div1 in my database. The code works if I run less than 20000 rows. But the data set I use has more than 100,000 rows. If I run the whole data it stops and the following error occurs:
Msg 9421, Level 16, State 1, Line 1.
XML parsing: line 1, character 218, illegal name character
Is there a way to work this around?

Answer 1

XML has CDATA[] section to treat content as-is without parsing. There is no need for multiple REPLACE() function calls. Check it out.
SQL
-- DDL and sample data population, start
DECLARE #tbl TABLE (ID INT IDENTITY(1,1) PRIMARY KEY, Div1 VARCHAR(MAX));
INSERT INTO #tbl (Div1)
VALUES
('N,l,S,T,A,,<all>,,N,A,N,N,N,Y,Y,,Y,Y,Y,,AA,SA,Enterprise')
, ('M,,A,S,AS,SS,AS,N,N,N,N,Y,Y,Y,ENTERPRISE,S,,A')
, ('L,,A,D,S,A,A,AA,Y,Y,Y,YNN,N,N,N,N,A,AA,AD,D,D');
-- DDL and sample data population, end
SELECT [Id],
CAST('<x><![CDATA[' + REPLACE(Div1, ',', ']]></x><x><![CDATA[') + ']]></x>' AS XML).value('(/x/text())[10]', 'VARCHAR(MAX)') [Div2],
Div1
FROM #tbl;

Answer 2

You can create a function to split string like below:
CREATE FUNCTION dbo.split_delimited_string
(
#list varchar(max),
#delimiter varchar(5)
)
RETURNS #items TABLE
(
pos_id int identity(1,1),
item varchar(255)
)
AS
BEGIN
DECLARE #pos int, #delimiter_len tinyint;
SET #pos = CHARINDEX(#delimiter,#list);
SET #delimiter_len=LEN(#delimiter);
WHILE (#pos>0)
BEGIN
INSERT INTO #items (item)
SELECT LEFT(#list,#pos - 1)
SET #list = RIGHT(#list,LEN(#list) - #pos - #delimiter_len + 1);
SET #pos = CHARINDEX(#delimiter,#list);
END
IF #list<>N''
BEGIN
INSERT INTO #items (item)
SELECT #list;
END
RETURN;
END
The following query will return the content in the 10th position:
SELECT
t.[Id],
l.item AS Div2
t.Div1
FROM [dbo].[database] t
CROSS APPLY dbo.split_delimited_string(t.Div1,',') l
WHERE l.pos_id = 10;