Ggtcf

Finally, the wait is over with SQL Server 2016. They have introduced the Split string function, STRING_SPLIT:

select OtherID, cs.Value --SplitData
from yourtable
cross apply STRING_SPLIT (Data, ',') cs

All the other methods to split string like XML, Tally table, while loop, etc.. have been blown away by this STRING_SPLIT function.

Here is an excellent article with performance comparison: Performance Surprises and Assumptions: STRING_SPLIT.

For older versions, using tally table here is one split string function(best possible approach)

CREATE FUNCTION [dbo].[DelimitedSplit8K]
 (@pString VARCHAR(8000), @pDelimiter CHAR(1))
RETURNS TABLE WITH SCHEMABINDING AS
 RETURN
--===== "Inline" CTE Driven "Tally Table" produces values from 0 up to 10,000...
 -- enough to cover NVARCHAR(4000)
 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
 ), --10E+1 or 10 rows
 E2(N) AS (SELECT 1 FROM E1 a, E1 b), --10E+2 or 100 rows
 E4(N) AS (SELECT 1 FROM E2 a, E2 b), --10E+4 or 10,000 rows max
 cteTally(N) AS (--==== This provides the "base" CTE and limits the number of rows right up front
 -- for both a performance gain and prevention of accidental "overruns"
 SELECT TOP (ISNULL(DATALENGTH(@pString),0)) ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM E4
 ),
cteStart(N1) AS (--==== This returns N+1 (starting position of each "element" just once for each delimiter)
 SELECT 1 UNION ALL
 SELECT t.N+1 FROM cteTally t WHERE SUBSTRING(@pString,t.N,1) = @pDelimiter
 ),
cteLen(N1,L1) AS(--==== Return start and length (for use in substring)
 SELECT s.N1,
 ISNULL(NULLIF(CHARINDEX(@pDelimiter,@pString,s.N1),0)-s.N1,8000)
 FROM cteStart s
 )
--===== Do the actual split. The ISNULL/NULLIF combo handles the length for the final element when no delimiter is found.
 SELECT ItemNumber = ROW_NUMBER() OVER(ORDER BY l.N1),
 Item = SUBSTRING(@pString, l.N1, l.L1)
 FROM cteLen l
;

Referred from Tally OH! An Improved SQL 8K “CSV Splitter” Function

Check this

 SELECT A.OtherID, 
 Split.a.value('.', 'VARCHAR(100)') AS Data 
 FROM 
 (
 SELECT OtherID, 
 CAST ('<M>' + REPLACE(Data, ',', '</M><M>') + '</M>' AS XML) AS Data 
 FROM Table1
 ) AS A CROSS APPLY Data.nodes ('/M') AS Split(a); 

select t.OtherID,x.Kod
 from testData t
 cross apply (select Code from dbo.Split(t.Data,',') ) x

As of Feb 2016 - see the TALLY Table Example - very likely to outperform my TVF below, from Feb 2014. Keeping original post below for posterity:

Too much repeated code for my liking in the above examples. And I dislike the performance of CTEs and XML. Also, an explicit Id so that consumers that are order specific can specify an ORDER BY clause.

CREATE FUNCTION dbo.Split
(
 @Line nvarchar(MAX),
 @SplitOn nvarchar(5) = ','
)
RETURNS @RtnValue table
(
 Id INT NOT NULL IDENTITY(1,1) PRIMARY KEY CLUSTERED,
 Data nvarchar(100) NOT NULL
)
AS
BEGIN
 IF @Line IS NULL RETURN

 DECLARE @split_on_len INT = LEN(@SplitOn)
 DECLARE @start_at INT = 1
 DECLARE @end_at INT
 DECLARE @data_len INT

 WHILE 1=1
 BEGIN
 SET @end_at = CHARINDEX(@SplitOn,@Line,@start_at)
 SET @data_len = CASE @end_at WHEN 0 THEN LEN(@Line) ELSE @end_at-@start_at END
 INSERT INTO @RtnValue (data) VALUES( SUBSTRING(@Line,@start_at,@data_len) );
 IF @end_at = 0 BREAK;
 SET @start_at = @end_at + @split_on_len
 END

 RETURN
END

Nice to see that it have been solved in the 2016 version, but for all of those that is not on that, here are two generalized and simplified versions of the methods above.

The XML-method is shorter, but of course requires the string to allow for the xml-trick (no 'bad' chars.)

XML-Method:

create function dbo.splitString(@input Varchar(max), @Splitter VarChar(99)) returns table as
Return
 SELECT Split.a.value('.', 'VARCHAR(max)') AS Data FROM
 ( SELECT CAST ('<M>' + REPLACE(@input, @Splitter, '</M><M>') + '</M>' AS XML) AS Data 
 ) AS A CROSS APPLY Data.nodes ('/M') AS Split(a); 

Recursive method:

create function dbo.splitString(@input Varchar(max), @Splitter Varchar(99)) returns table as
Return
 with tmp (DataItem, ix) as
 ( select @input , CHARINDEX('',@Input) --Recu. start, ignored val to get the types right
 union all
 select Substring(@input, ix+1,ix2-ix-1), ix2
 from (Select *, CHARINDEX(@Splitter,@Input+@Splitter,ix+1) ix2 from tmp) x where ix2<>0
 ) select DataItem from tmp where ix<>0

Function in action

Create table TEST_X (A int, CSV Varchar(100));
Insert into test_x select 1, 'A,B';
Insert into test_x select 2, 'C,D';

Select A,data from TEST_X x cross apply dbo.splitString(x.CSV,',') Y;

Drop table TEST_X

XML-METHOD 2: Unicode Friendly 😀 (Addition courtesy of Max Hodges)

create function dbo.splitString(@input nVarchar(max), @Splitter nVarchar(99)) returns table as
Return
SELECT Split.a.value('.', 'NVARCHAR(max)') AS Data FROM
( SELECT CAST ('<M>' + REPLACE(@input, @Splitter, '</M><M>') + '</M>' AS XML) AS Data
) AS A CROSS APPLY Data.nodes ('/M') AS Split(a);


DECLARE @id_list VARCHAR(MAX) = '1234,23,56,576,1231,567,122,87876,57553,1216'
DECLARE @table TABLE ( id VARCHAR(50) )
DECLARE @x INT = 0
DECLARE @firstcomma INT = 0
DECLARE @nextcomma INT = 0

SET @x = LEN(@id_list) - LEN(REPLACE(@id_list, ',', '')) + 1 -- number of ids in id_list

WHILE @x > 0
 BEGIN
 SET @nextcomma = CASE WHEN CHARINDEX(',', @id_list, @firstcomma + 1) = 0
 THEN LEN(@id_list) + 1
 ELSE CHARINDEX(',', @id_list, @firstcomma + 1)
 END
 INSERT INTO @table
 VALUES ( SUBSTRING(@id_list, @firstcomma + 1, (@nextcomma - @firstcomma) - 1) )
 SET @firstcomma = CHARINDEX(',', @id_list, @firstcomma + 1)
 SET @x = @x - 1
 END

SELECT *
FROM @table

When using this approach you have to make sure that none of your values contains something that would be illegal XML – user1151923

I always use the XML method. Make sure you use VALID XML. I have two functions to convert between valid XML and Text. (I tend to strip out the carriage returns as I don't usually need them.

CREATE FUNCTION dbo.udf_ConvertTextToXML (@Text varchar(MAX)) 
 RETURNS varchar(MAX)
AS
 BEGIN
 SET @Text = REPLACE(@Text,CHAR(10),'')
 SET @Text = REPLACE(@Text,CHAR(13),'')
 SET @Text = REPLACE(@Text,'<','&lt;')
 SET @Text = REPLACE(@Text,'&','&amp;')
 SET @Text = REPLACE(@Text,'>','&gt;')
 SET @Text = REPLACE(@Text,'''','&apos;')
 SET @Text = REPLACE(@Text,'"','&quot;')
 RETURN @Text
END


CREATE FUNCTION dbo.udf_ConvertTextFromXML (@Text VARCHAR(MAX)) 
 RETURNS VARCHAR(max)
AS
 BEGIN
 SET @Text = REPLACE(@Text,'&lt;','<')
 SET @Text = REPLACE(@Text,'&amp;','&')
 SET @Text = REPLACE(@Text,'&gt;','>')
 SET @Text = REPLACE(@Text,'&apos;','''')
 SET @Text = REPLACE(@Text,'&quot;','"')
 RETURN @Text
END

Function

CREATE FUNCTION dbo.SplitToRows (@column varchar(100), @separator varchar(10))
RETURNS @rtnTable TABLE
 (
 ID int identity(1,1),
 ColumnA varchar(max)
 )
 AS
BEGIN
 DECLARE @position int = 0
 DECLARE @endAt int = 0
 DECLARE @tempString varchar(100)

 set @column = ltrim(rtrim(@column))

 WHILE @position<=len(@column)
 BEGIN 
 set @endAt = CHARINDEX(@separator,@column,@position)
 if(@endAt=0)
 begin
 Insert into @rtnTable(ColumnA) Select substring(@column,@position,len(@column)-@position)
 break;
 end
 set @tempString = substring(ltrim(rtrim(@column)),@position,@endAt-@position)

 Insert into @rtnTable(ColumnA) select @tempString
 set @position=@endAt+1;
 END
 return
END

Use case

select * from dbo.SplitToRows('T14; p226.0001; eee; 3554;', ';')

Or just a select with multiple result set

DECLARE @column varchar(max)= '1234; 4748;abcde; 324432'
DECLARE @separator varchar(10) = ';'
DECLARE @position int = 0
DECLARE @endAt int = 0
DECLARE @tempString varchar(100)

set @column = ltrim(rtrim(@column))

WHILE @position<=len(@column)
BEGIN 
 set @endAt = CHARINDEX(@separator,@column,@position)
 if(@endAt=0)
 begin
 Select substring(@column,@position,len(@column)-@position)
 break;
 end
 set @tempString = substring(ltrim(rtrim(@column)),@position,@endAt-@position)

 select @tempString
 set @position=@endAt+1;
END

Please refer below TSQL. STRING_SPLIT function is available only under compatibility level 130 and above.

TSQL:

DECLARE @stringValue NVARCHAR(400) = 'red,blue,green,yellow,black' 
DECLARE @separator CHAR = ','

SELECT [value] As Colour
FROM STRING_SPLIT(@stringValue, @separator); 

RESULT:

Colour

red
blue
green
yellow
black

Very late but try this out:

SELECT ColumnID, Column1, value --Do not change 'value' name. Leave it as it is.
FROM tbl_Sample 
CROSS APPLY STRING_SPLIT(Tags, ','); --'Tags' is the name of column containing comma separated values

So we were having this:
tbl_Sample :

ColumnID| Column1 | Tags
--------|-----------|-------------
1 | ABC | 10,11,12 
2 | PQR | 20,21,22

After running this query:

ColumnID| Column1 | value
--------|-----------|-----------
1 | ABC | 10
1 | ABC | 11
1 | ABC | 12
2 | PQR | 20
2 | PQR | 21
2 | PQR | 22

Thanks!

;WITH tmp(SomeID, OtherID, DataItem, Data) as (
 SELECT SomeID, OtherID, LEFT(Data, CHARINDEX(',',Data+',')-1),
 STUFF(Data, 1, CHARINDEX(',',Data+','), '')
FROM Testdata
WHERE Data > ''
)
SELECT SomeID, OtherID, Data
FROM tmp
ORDER BY SomeID

with only tiny little modification to above query...

Below works on sql server 2008

select *, ROW_NUMBER() OVER(order by items) as row# 
from 
( select 134 myColumn1, 34 myColumn2, 'd,c,k,e,f,g,h,a' comaSeperatedColumn) myTable
 cross apply 
SPLIT (rtrim(comaSeperatedColumn), ',') splitedTable -- gives 'items' column 

Will get all Cartesian product with the origin table columns plus "items" of split table.

You can use the following function to extract data

CREATE FUNCTION [dbo].[SplitString]
( 
 @RowData NVARCHAR(MAX),
 @Delimeter NVARCHAR(MAX)
)
RETURNS @RtnValue TABLE 
(
 ID INT IDENTITY(1,1),
 Data NVARCHAR(MAX)
) 
AS
BEGIN 
 DECLARE @Iterator INT
 SET @Iterator = 1

 DECLARE @FoundIndex INT
 SET @FoundIndex = CHARINDEX(@Delimeter,@RowData)

 WHILE (@FoundIndex>0)
 BEGIN
 INSERT INTO @RtnValue (data)
 SELECT 
 Data = LTRIM(RTRIM(SUBSTRING(@RowData, 1, @FoundIndex - 1)))

 SET @RowData = SUBSTRING(@RowData,
 @FoundIndex + DATALENGTH(@Delimeter) / 2,
 LEN(@RowData))

 SET @Iterator = @Iterator + 1
 SET @FoundIndex = CHARINDEX(@Delimeter, @RowData)
 END

 INSERT INTO @RtnValue (Data)
 SELECT Data = LTRIM(RTRIM(@RowData))

 RETURN
END