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I have a need to create a function the will return nth element of a delimited string.
For a data migration project, I am converting JSON audit records stored in a SQL Server database into a structured report using SQL script. Goal is to deliver a sql script and a sql function used by the script without any code.
(This is a short-term fix will be used while a new auditing feature is added the ASP.NET/MVC application)
There is no shortage of delimited string to table examples available.
I've chosen a Common Table Expression example http://www.sqlperformance.com/2012/07/t-sql-queries/split-strings
Example: I want to return 67 from '1,222,2,67,888,1111'
This is the easiest answer to rerieve the 67 (type-safe!!):
SELECT CAST('<x>' + REPLACE('1,222,2,67,888,1111',',','</x><x>') + '</x>' AS XML).value('/x[4]','int')
In the following you will find examples how to use this with variables for the string, the delimiter and the position (even for edge-cases with XML-forbidden characters)
The easy one
This question is not about a string split approach, but about how to get the nth element. The easiest, fully inlineable way would be this IMO:
This is a real one-liner to get part 2 delimited by a space:
DECLARE #input NVARCHAR(100)=N'part1 part2 part3';
SELECT CAST(N'<x>' + REPLACE(#input,N' ',N'</x><x>') + N'</x>' AS XML).value('/x[2]','nvarchar(max)')
Variables can be used with sql:variable() or sql:column()
Of course you can use variables for delimiter and position (use sql:column to retrieve the position directly from a query's value):
DECLARE #dlmt NVARCHAR(10)=N' ';
DECLARE #pos INT = 2;
SELECT CAST(N'<x>' + REPLACE(#input,#dlmt,N'</x><x>') + N'</x>' AS XML).value('/x[sql:variable("#pos")][1]','nvarchar(max)')
Edge-Case with XML-forbidden characters
If your string might include forbidden characters, you still can do it this way. Just use FOR XML PATH on your string first to replace all forbidden characters with the fitting escape sequence implicitly.
It's a very special case if - additionally - your delimiter is the semicolon. In this case I replace the delimiter first to '#DLMT#', and replace this to the XML tags finally:
SET #input=N'Some <, > and &;Other äöü#€;One more';
SET #dlmt=N';';
SELECT CAST(N'<x>' + REPLACE((SELECT REPLACE(#input,#dlmt,'#DLMT#') AS [*] FOR XML PATH('')),N'#DLMT#',N'</x><x>') + N'</x>' AS XML).value('/x[sql:variable("#pos")][1]','nvarchar(max)');
UPDATE for SQL-Server 2016+
Regretfully the developers forgot to return the part's index with STRING_SPLIT. But, using SQL-Server 2016+, there is JSON_VALUE and OPENJSON.
With JSON_VALUE we can pass in the position as the index' array.
For OPENJSON the documentation states clearly:
When OPENJSON parses a JSON array, the function returns the indexes of the elements in the JSON text as keys.
A string like 1,2,3 needs nothing more than brackets: [1,2,3].
A string of words like this is an example needs to be ["this","is","an"," example"].
These are very easy string operations. Just try it out:
DECLARE #str VARCHAR(100)='Hello John Smith';
DECLARE #position INT = 2;
--We can build the json-path '$[1]' using CONCAT
SELECT JSON_VALUE('["' + REPLACE(#str,' ','","') + '"]',CONCAT('$[',#position-1,']'));
--See this for a position safe string-splitter (zero-based):
SELECT JsonArray.[key] AS [Position]
,JsonArray.[value] AS [Part]
FROM OPENJSON('["' + REPLACE(#str,' ','","') + '"]') JsonArray
In this post I tested various approaches and found, that OPENJSON is really fast. Even much faster than the famous "delimitedSplit8k()" method...
UPDATE 2 - Get the values type-safe
We can use an array within an array simply by using doubled [[]]. This allows for a typed WITH-clause:
DECLARE #SomeDelimitedString VARCHAR(100)='part1|1|20190920';
DECLARE #JsonArray NVARCHAR(MAX)=CONCAT('[["',REPLACE(#SomeDelimitedString,'|','","'),'"]]');
SELECT #SomeDelimitedString AS TheOriginal
,#JsonArray AS TransformedToJSON
,ValuesFromTheArray.*
FROM OPENJSON(#JsonArray)
WITH(TheFirstFragment VARCHAR(100) '$[0]'
,TheSecondFragment INT '$[1]'
,TheThirdFragment DATE '$[2]') ValuesFromTheArray
Here is my initial solution...
It is based on work by Aaron Bertrand http://www.sqlperformance.com/2012/07/t-sql-queries/split-strings
I simply changed the return type to make it a scalar function.
Example:
SELECT dbo.GetSplitString_CTE('1,222,2,67,888,1111',',',4)
CREATE FUNCTION dbo.GetSplitString_CTE
(
#List VARCHAR(MAX),
#Delimiter VARCHAR(255),
#ElementNumber int
)
RETURNS VARCHAR(4000)
AS
BEGIN
DECLARE #result varchar(4000)
DECLARE #Items TABLE ( position int IDENTITY PRIMARY KEY,
Item VARCHAR(4000)
)
DECLARE #ll INT = LEN(#List) + 1, #ld INT = LEN(#Delimiter);
WITH a AS
(
SELECT
[start] = 1,
[end] = COALESCE(NULLIF(CHARINDEX(#Delimiter,
#List, #ld), 0), #ll),
[value] = SUBSTRING(#List, 1,
COALESCE(NULLIF(CHARINDEX(#Delimiter,
#List, #ld), 0), #ll) - 1)
UNION ALL
SELECT
[start] = CONVERT(INT, [end]) + #ld,
[end] = COALESCE(NULLIF(CHARINDEX(#Delimiter,
#List, [end] + #ld), 0), #ll),
[value] = SUBSTRING(#List, [end] + #ld,
COALESCE(NULLIF(CHARINDEX(#Delimiter,
#List, [end] + #ld), 0), #ll)-[end]-#ld)
FROM a
WHERE [end] < #ll
)
INSERT #Items SELECT [value]
FROM a
WHERE LEN([value]) > 0
OPTION (MAXRECURSION 0);
SELECT #result=Item
FROM #Items
WHERE position=#ElementNumber
RETURN #result;
END
GO
How about:
CREATE FUNCTION dbo.NTH_ELEMENT (#Input NVARCHAR(MAX), #Delim CHAR = '-', #N INT = 0)
RETURNS NVARCHAR(MAX)
AS
BEGIN
RETURN (SELECT VALUE FROM STRING_SPLIT(#Input, #Delim) ORDER BY (SELECT NULL) OFFSET #N ROWS FETCH NEXT 1 ROW ONLY)
END
On Azure SQL Database, and on SQL Server 2022, STRING_SPLIT now has an optional ordinal parameter. If the parameter is omitted, or 0 is passed, then the function acts as it did before, and just returns a value column and the order is not guaranteed. If you pass the parameter with the value 1 then the function returns 2 columns, value, and ordinal which (unsurprisingly) provides the ordinal position of the value within the string.
So, if you wanted the 4th delimited value from the string '1,222,2,67,888,1111' you could do the following:
SELECT [value]
FROM STRING_SPLIT('1,222,2,67,888,1111',',',1)
WHERE ordinal = 4;
If the value was in a column, it would look like this:
SELECT SS.[value]
FROM dbo.YourTable YT
CROSS APPLY STRING_SPLIT(YT.YourColumn,',',1) SS
WHERE SS.ordinal = 4;
#a - the value (f.e. 'a/bb/ccc/dddd/ee/ff/....')
#p - the desired position (1,2,3...)
#d - the delimeter ( '/' )
trim(substring(replace(#a,#d,replicate(' ',len(#a))),(#p-1)*len(#a)+1,len(#a)))
only problem is - if desired part has trailing or leading blanks they get trimmed.
Completely Based on article from https://exceljet.net/formula/split-text-with-delimiter
In a rare moment of lunacy I just thought that split is far easier if we use XML to parse it out for us:
(Using the variables from #Gary Kindel's answer)
declare #xml xml
set #xml = '<split><el>' + replace(#list,#Delimiter,'</el><el>') + '</el></split>'
select
el = split.el.value('.','varchar(max)')
from #xml.nodes('/split/el') split(el))
This lists all elements of the string, split by the specified character.
We can use an xpath test to filter out empty values, and a further xpath test to restrict this to the element we're interested in. In full Gary's function becomes:
alter FUNCTION dbo.GetSplitString_CTE
(
#List VARCHAR(MAX),
#Delimiter VARCHAR(255),
#ElementNumber int
)
RETURNS VARCHAR(max)
AS
BEGIN
-- escape any XML https://dba.stackexchange.com/a/143140/65992
set #list = convert(VARCHAR(MAX),(select #list for xml path(''), type));
declare #xml xml
set #xml = '<split><el>' + replace(#list,#Delimiter,'</el><el>') + '</el></split>'
declare #ret varchar(max)
set #ret = (select
el = split.el.value('.','varchar(max)')
from #xml.nodes('/split/el[string-length(.)>0][position() = sql:variable("#elementnumber")]') split(el))
return #ret
END
you can put this select into UFN. if you need you can customize it for specifying delimiter as well. in that case your ufn will have two input. number Nth and delimiter to use.
DECLARE #tlist varchar(max)='10,20,30,40,50,60,70,80,90,100'
DECLARE #i INT=1, #nth INT=3
While len(#tlist) <> 0
BEGIN
IF #i=#nth
BEGIN
select Case when charindex(',',#tlist) <> 0 Then LEFT(#tlist,charindex(',',#tlist)-1)
Else #tlist
END
END
Select #tlist = Case when charindex(',',#tlist) <> 0 Then substring(#tlist,charindex(',',#tlist)+1,len(#tlist))
Else ''
END
SELECT #i=#i+1
END
Alternatively, one can use xml, nodes() and ROW_NUMBER. We can order the elements based on their document order. For example:
DECLARE #Input VARCHAR(100) = '1a,2b,3c,4d,5e,6f,7g,8h'
,#Number TINYINT = 3
DECLARE #XML XML;
DECLARE #value VARCHAR(100);
SET #XML = CAST('<x>' + REPLACE(#Input,',','</x><x>') + '</x>' AS XML);
WITH DataSource ([rowID], [rowValue]) AS
(
SELECT ROW_NUMBER() OVER (ORDER BY T.c ASC)
,T.c.value('.', 'VARCHAR(100)')
FROM #XML.nodes('./x') T(c)
)
SELECT #value = [rowValue]
FROM DataSource
WHERE [rowID] = #Number;
SELECT #value;
I would rather create a temp table with an identity column and fill it up with output from the SPLIT function.
CREATE TABLE #tblVals(Id INT IDENTITY(1,1), Val NVARCHAR(100))
INSERT INTO #tblVals (Val)
SELECT [value] FROM STRING_SPLIT('Val1-Val3-Val2-Val5', '-')
SELECT * FROM #tblVals
Now you can easily do something like below.
DECLARE #val2 NVARCHAR(100) = (SELECT TOP 1 Val FROM #tblVals WHERE Id = 2)
See the snapshot below:
You can use STRING_SPLIT with ROW_NUMBER:
SELECT value, idx FROM
(
SELECT
value,
ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) idx
FROM STRING_SPLIT('Lorem ipsum dolor sit amet.', ' ')
) t
WHERE idx=2
returns second element (idx=2): 'ipsum'
We have the answer over below url.
DECLARE # AS VARCHAR(MAX) = 'Pawan1,Pawan2,Pawan4,Pawan3'
SELECT VALUE FROM
(
SELECT VALUE , ROW_NUMBER() OVER (ORDER BY (SELECT null)) rnk FROM STRING_SPLIT(#, ',')
)x where rnk = 3
GO
https://msbiskills.com/2018/06/15/sql-puzzle-multiple-ways-to-split-a-string-and-get-nth-row-xml-advanced-sql/
I don't have enough reputation to comment, so I am adding an answer. Please adjust as appropriate.
I have a problem with Gary Kindel's answer for cases where there is nothing between the two delimiters
If you do
select * from dbo.GetSplitString_CTE('abc^def^^ghi','^',3)
you get
ghi
instead of an empty string
If you comment out the
WHERE LEN([value]) > 0
line, you get the desired result
I cannot comment on Gary's solution because of my low reputation
I know Gary was referencing another link.
I have struggled to understand why we need this variable
#ld INT = LEN(#Delimiter)
I also don't understand why charindex has to start at the position of length of delimiter, #ld
I tested with many examples with a single character delimiter, and they work. Most of the time, delimiter character is a single character. However, since the developer included the ld as length of delimiter, the code has to work for delimiters that have more than one character
In this case, the following case will fail
11,,,22,,,33,,,44,,,55,,,
I cloned from the codes from this link. http://codebetter.com/raymondlewallen/2005/10/26/quick-t-sql-to-parse-a-delimited-string/
I have tested various scenarios including the delimiters that have more than one character
alter FUNCTION [dbo].[split1]
(
#string1 VARCHAR(8000) -- List of delimited items
, #Delimiter VARCHAR(40) = ',' -- delimiter that separates items
, #ElementNumber int
)
RETURNS varchar(8000)
AS
BEGIN
declare #position int
declare #piece varchar(8000)=''
declare #returnVal varchar(8000)=''
declare #Pattern varchar(50) = '%' + #Delimiter + '%'
declare #counter int =0
declare #ld int = len(#Delimiter)
declare #ls1 int = len (#string1)
declare #foundit int = 0
if patindex(#Pattern , #string1) = 0
return ''
if right(rtrim(#string1),1) <> #Delimiter
set #string1 = #string1 + #Delimiter
set #position = patindex(#Pattern , #string1) + #ld -1
while #position > 0
begin
set #counter = #counter +1
set #ls1 = len (#string1)
if (#ls1 >= #ld)
set #piece = left(#string1, #position - #ld)
else
break
if (#counter = #ElementNumber)
begin
set #foundit = 1
break
end
if len(#string1) > 0
begin
set #string1 = stuff(#string1, 1, #position, '')
set #position = patindex(#Pattern , #string1) + #ld -1
end
else
set #position = -1
end
if #foundit =1
set #returnVal = #piece
else
set #returnVal = ''
return #returnVal
you can create simple table variable and use it as below
Declare #tbl_split Table (Id INT IDENTITY(1,1), VAL VARCHAR(50))
INSERT #tbl_split SELECT VALUE
FROM string_split('999999:01', ':')
Select val from #tbl_split
WHERE Id=2
I have a need to create a function the will return nth element of a delimited string.
For a data migration project, I am converting JSON audit records stored in a SQL Server database into a structured report using SQL script. Goal is to deliver a sql script and a sql function used by the script without any code.
(This is a short-term fix will be used while a new auditing feature is added the ASP.NET/MVC application)
There is no shortage of delimited string to table examples available.
I've chosen a Common Table Expression example http://www.sqlperformance.com/2012/07/t-sql-queries/split-strings
Example: I want to return 67 from '1,222,2,67,888,1111'
This is the easiest answer to rerieve the 67 (type-safe!!):
SELECT CAST('<x>' + REPLACE('1,222,2,67,888,1111',',','</x><x>') + '</x>' AS XML).value('/x[4]','int')
In the following you will find examples how to use this with variables for the string, the delimiter and the position (even for edge-cases with XML-forbidden characters)
The easy one
This question is not about a string split approach, but about how to get the nth element. The easiest, fully inlineable way would be this IMO:
This is a real one-liner to get part 2 delimited by a space:
DECLARE #input NVARCHAR(100)=N'part1 part2 part3';
SELECT CAST(N'<x>' + REPLACE(#input,N' ',N'</x><x>') + N'</x>' AS XML).value('/x[2]','nvarchar(max)')
Variables can be used with sql:variable() or sql:column()
Of course you can use variables for delimiter and position (use sql:column to retrieve the position directly from a query's value):
DECLARE #dlmt NVARCHAR(10)=N' ';
DECLARE #pos INT = 2;
SELECT CAST(N'<x>' + REPLACE(#input,#dlmt,N'</x><x>') + N'</x>' AS XML).value('/x[sql:variable("#pos")][1]','nvarchar(max)')
Edge-Case with XML-forbidden characters
If your string might include forbidden characters, you still can do it this way. Just use FOR XML PATH on your string first to replace all forbidden characters with the fitting escape sequence implicitly.
It's a very special case if - additionally - your delimiter is the semicolon. In this case I replace the delimiter first to '#DLMT#', and replace this to the XML tags finally:
SET #input=N'Some <, > and &;Other äöü#€;One more';
SET #dlmt=N';';
SELECT CAST(N'<x>' + REPLACE((SELECT REPLACE(#input,#dlmt,'#DLMT#') AS [*] FOR XML PATH('')),N'#DLMT#',N'</x><x>') + N'</x>' AS XML).value('/x[sql:variable("#pos")][1]','nvarchar(max)');
UPDATE for SQL-Server 2016+
Regretfully the developers forgot to return the part's index with STRING_SPLIT. But, using SQL-Server 2016+, there is JSON_VALUE and OPENJSON.
With JSON_VALUE we can pass in the position as the index' array.
For OPENJSON the documentation states clearly:
When OPENJSON parses a JSON array, the function returns the indexes of the elements in the JSON text as keys.
A string like 1,2,3 needs nothing more than brackets: [1,2,3].
A string of words like this is an example needs to be ["this","is","an"," example"].
These are very easy string operations. Just try it out:
DECLARE #str VARCHAR(100)='Hello John Smith';
DECLARE #position INT = 2;
--We can build the json-path '$[1]' using CONCAT
SELECT JSON_VALUE('["' + REPLACE(#str,' ','","') + '"]',CONCAT('$[',#position-1,']'));
--See this for a position safe string-splitter (zero-based):
SELECT JsonArray.[key] AS [Position]
,JsonArray.[value] AS [Part]
FROM OPENJSON('["' + REPLACE(#str,' ','","') + '"]') JsonArray
In this post I tested various approaches and found, that OPENJSON is really fast. Even much faster than the famous "delimitedSplit8k()" method...
UPDATE 2 - Get the values type-safe
We can use an array within an array simply by using doubled [[]]. This allows for a typed WITH-clause:
DECLARE #SomeDelimitedString VARCHAR(100)='part1|1|20190920';
DECLARE #JsonArray NVARCHAR(MAX)=CONCAT('[["',REPLACE(#SomeDelimitedString,'|','","'),'"]]');
SELECT #SomeDelimitedString AS TheOriginal
,#JsonArray AS TransformedToJSON
,ValuesFromTheArray.*
FROM OPENJSON(#JsonArray)
WITH(TheFirstFragment VARCHAR(100) '$[0]'
,TheSecondFragment INT '$[1]'
,TheThirdFragment DATE '$[2]') ValuesFromTheArray
Here is my initial solution...
It is based on work by Aaron Bertrand http://www.sqlperformance.com/2012/07/t-sql-queries/split-strings
I simply changed the return type to make it a scalar function.
Example:
SELECT dbo.GetSplitString_CTE('1,222,2,67,888,1111',',',4)
CREATE FUNCTION dbo.GetSplitString_CTE
(
#List VARCHAR(MAX),
#Delimiter VARCHAR(255),
#ElementNumber int
)
RETURNS VARCHAR(4000)
AS
BEGIN
DECLARE #result varchar(4000)
DECLARE #Items TABLE ( position int IDENTITY PRIMARY KEY,
Item VARCHAR(4000)
)
DECLARE #ll INT = LEN(#List) + 1, #ld INT = LEN(#Delimiter);
WITH a AS
(
SELECT
[start] = 1,
[end] = COALESCE(NULLIF(CHARINDEX(#Delimiter,
#List, #ld), 0), #ll),
[value] = SUBSTRING(#List, 1,
COALESCE(NULLIF(CHARINDEX(#Delimiter,
#List, #ld), 0), #ll) - 1)
UNION ALL
SELECT
[start] = CONVERT(INT, [end]) + #ld,
[end] = COALESCE(NULLIF(CHARINDEX(#Delimiter,
#List, [end] + #ld), 0), #ll),
[value] = SUBSTRING(#List, [end] + #ld,
COALESCE(NULLIF(CHARINDEX(#Delimiter,
#List, [end] + #ld), 0), #ll)-[end]-#ld)
FROM a
WHERE [end] < #ll
)
INSERT #Items SELECT [value]
FROM a
WHERE LEN([value]) > 0
OPTION (MAXRECURSION 0);
SELECT #result=Item
FROM #Items
WHERE position=#ElementNumber
RETURN #result;
END
GO
How about:
CREATE FUNCTION dbo.NTH_ELEMENT (#Input NVARCHAR(MAX), #Delim CHAR = '-', #N INT = 0)
RETURNS NVARCHAR(MAX)
AS
BEGIN
RETURN (SELECT VALUE FROM STRING_SPLIT(#Input, #Delim) ORDER BY (SELECT NULL) OFFSET #N ROWS FETCH NEXT 1 ROW ONLY)
END
On Azure SQL Database, and on SQL Server 2022, STRING_SPLIT now has an optional ordinal parameter. If the parameter is omitted, or 0 is passed, then the function acts as it did before, and just returns a value column and the order is not guaranteed. If you pass the parameter with the value 1 then the function returns 2 columns, value, and ordinal which (unsurprisingly) provides the ordinal position of the value within the string.
So, if you wanted the 4th delimited value from the string '1,222,2,67,888,1111' you could do the following:
SELECT [value]
FROM STRING_SPLIT('1,222,2,67,888,1111',',',1)
WHERE ordinal = 4;
If the value was in a column, it would look like this:
SELECT SS.[value]
FROM dbo.YourTable YT
CROSS APPLY STRING_SPLIT(YT.YourColumn,',',1) SS
WHERE SS.ordinal = 4;
#a - the value (f.e. 'a/bb/ccc/dddd/ee/ff/....')
#p - the desired position (1,2,3...)
#d - the delimeter ( '/' )
trim(substring(replace(#a,#d,replicate(' ',len(#a))),(#p-1)*len(#a)+1,len(#a)))
only problem is - if desired part has trailing or leading blanks they get trimmed.
Completely Based on article from https://exceljet.net/formula/split-text-with-delimiter
In a rare moment of lunacy I just thought that split is far easier if we use XML to parse it out for us:
(Using the variables from #Gary Kindel's answer)
declare #xml xml
set #xml = '<split><el>' + replace(#list,#Delimiter,'</el><el>') + '</el></split>'
select
el = split.el.value('.','varchar(max)')
from #xml.nodes('/split/el') split(el))
This lists all elements of the string, split by the specified character.
We can use an xpath test to filter out empty values, and a further xpath test to restrict this to the element we're interested in. In full Gary's function becomes:
alter FUNCTION dbo.GetSplitString_CTE
(
#List VARCHAR(MAX),
#Delimiter VARCHAR(255),
#ElementNumber int
)
RETURNS VARCHAR(max)
AS
BEGIN
-- escape any XML https://dba.stackexchange.com/a/143140/65992
set #list = convert(VARCHAR(MAX),(select #list for xml path(''), type));
declare #xml xml
set #xml = '<split><el>' + replace(#list,#Delimiter,'</el><el>') + '</el></split>'
declare #ret varchar(max)
set #ret = (select
el = split.el.value('.','varchar(max)')
from #xml.nodes('/split/el[string-length(.)>0][position() = sql:variable("#elementnumber")]') split(el))
return #ret
END
you can put this select into UFN. if you need you can customize it for specifying delimiter as well. in that case your ufn will have two input. number Nth and delimiter to use.
DECLARE #tlist varchar(max)='10,20,30,40,50,60,70,80,90,100'
DECLARE #i INT=1, #nth INT=3
While len(#tlist) <> 0
BEGIN
IF #i=#nth
BEGIN
select Case when charindex(',',#tlist) <> 0 Then LEFT(#tlist,charindex(',',#tlist)-1)
Else #tlist
END
END
Select #tlist = Case when charindex(',',#tlist) <> 0 Then substring(#tlist,charindex(',',#tlist)+1,len(#tlist))
Else ''
END
SELECT #i=#i+1
END
Alternatively, one can use xml, nodes() and ROW_NUMBER. We can order the elements based on their document order. For example:
DECLARE #Input VARCHAR(100) = '1a,2b,3c,4d,5e,6f,7g,8h'
,#Number TINYINT = 3
DECLARE #XML XML;
DECLARE #value VARCHAR(100);
SET #XML = CAST('<x>' + REPLACE(#Input,',','</x><x>') + '</x>' AS XML);
WITH DataSource ([rowID], [rowValue]) AS
(
SELECT ROW_NUMBER() OVER (ORDER BY T.c ASC)
,T.c.value('.', 'VARCHAR(100)')
FROM #XML.nodes('./x') T(c)
)
SELECT #value = [rowValue]
FROM DataSource
WHERE [rowID] = #Number;
SELECT #value;
I would rather create a temp table with an identity column and fill it up with output from the SPLIT function.
CREATE TABLE #tblVals(Id INT IDENTITY(1,1), Val NVARCHAR(100))
INSERT INTO #tblVals (Val)
SELECT [value] FROM STRING_SPLIT('Val1-Val3-Val2-Val5', '-')
SELECT * FROM #tblVals
Now you can easily do something like below.
DECLARE #val2 NVARCHAR(100) = (SELECT TOP 1 Val FROM #tblVals WHERE Id = 2)
See the snapshot below:
You can use STRING_SPLIT with ROW_NUMBER:
SELECT value, idx FROM
(
SELECT
value,
ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) idx
FROM STRING_SPLIT('Lorem ipsum dolor sit amet.', ' ')
) t
WHERE idx=2
returns second element (idx=2): 'ipsum'
We have the answer over below url.
DECLARE # AS VARCHAR(MAX) = 'Pawan1,Pawan2,Pawan4,Pawan3'
SELECT VALUE FROM
(
SELECT VALUE , ROW_NUMBER() OVER (ORDER BY (SELECT null)) rnk FROM STRING_SPLIT(#, ',')
)x where rnk = 3
GO
https://msbiskills.com/2018/06/15/sql-puzzle-multiple-ways-to-split-a-string-and-get-nth-row-xml-advanced-sql/
I don't have enough reputation to comment, so I am adding an answer. Please adjust as appropriate.
I have a problem with Gary Kindel's answer for cases where there is nothing between the two delimiters
If you do
select * from dbo.GetSplitString_CTE('abc^def^^ghi','^',3)
you get
ghi
instead of an empty string
If you comment out the
WHERE LEN([value]) > 0
line, you get the desired result
I cannot comment on Gary's solution because of my low reputation
I know Gary was referencing another link.
I have struggled to understand why we need this variable
#ld INT = LEN(#Delimiter)
I also don't understand why charindex has to start at the position of length of delimiter, #ld
I tested with many examples with a single character delimiter, and they work. Most of the time, delimiter character is a single character. However, since the developer included the ld as length of delimiter, the code has to work for delimiters that have more than one character
In this case, the following case will fail
11,,,22,,,33,,,44,,,55,,,
I cloned from the codes from this link. http://codebetter.com/raymondlewallen/2005/10/26/quick-t-sql-to-parse-a-delimited-string/
I have tested various scenarios including the delimiters that have more than one character
alter FUNCTION [dbo].[split1]
(
#string1 VARCHAR(8000) -- List of delimited items
, #Delimiter VARCHAR(40) = ',' -- delimiter that separates items
, #ElementNumber int
)
RETURNS varchar(8000)
AS
BEGIN
declare #position int
declare #piece varchar(8000)=''
declare #returnVal varchar(8000)=''
declare #Pattern varchar(50) = '%' + #Delimiter + '%'
declare #counter int =0
declare #ld int = len(#Delimiter)
declare #ls1 int = len (#string1)
declare #foundit int = 0
if patindex(#Pattern , #string1) = 0
return ''
if right(rtrim(#string1),1) <> #Delimiter
set #string1 = #string1 + #Delimiter
set #position = patindex(#Pattern , #string1) + #ld -1
while #position > 0
begin
set #counter = #counter +1
set #ls1 = len (#string1)
if (#ls1 >= #ld)
set #piece = left(#string1, #position - #ld)
else
break
if (#counter = #ElementNumber)
begin
set #foundit = 1
break
end
if len(#string1) > 0
begin
set #string1 = stuff(#string1, 1, #position, '')
set #position = patindex(#Pattern , #string1) + #ld -1
end
else
set #position = -1
end
if #foundit =1
set #returnVal = #piece
else
set #returnVal = ''
return #returnVal
you can create simple table variable and use it as below
Declare #tbl_split Table (Id INT IDENTITY(1,1), VAL VARCHAR(50))
INSERT #tbl_split SELECT VALUE
FROM string_split('999999:01', ':')
Select val from #tbl_split
WHERE Id=2
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Closed 10 years ago.
Possible Duplicate:
Parameterizing an SQL IN clause?
I have a SQL function whereby I need to pass a list of IDs in, as a string, into:
WHERE ID IN (#MyList)
I have looked around and most of the answers are either where the SQL is built within C# and they loop through and call AddParameter, or the SQL is built dynamically.
My SQL function is fairly large and so building the query dynamically would be rather tedious.
Is there really no way to pass in a string of comma-separated values into the IN clause?
My variable being passed in is representing a list of integers so it would be:
"1,2,3,4,5,6,7" etc
Here is a slightly more efficient way to split a list of integers. First, create a numbers table, if you don't already have one. This will create a table with 100,000 unique integers (you may need more or less):
;WITH x AS
(
SELECT TOP (1000000) Number = ROW_NUMBER() OVER
(ORDER BY s1.[object_id])
FROM sys.all_objects AS s1 CROSS JOIN sys.all_objects AS s2
ORDER BY s1.[object_id]
)
SELECT Number INTO dbo.Numbers FROM x;
CREATE UNIQUE CLUSTERED INDEX n ON dbo.Numbers(Number);
Then a function:
CREATE FUNCTION [dbo].[SplitInts_Numbers]
(
#List NVARCHAR(MAX),
#Delimiter NVARCHAR(255)
)
RETURNS TABLE
WITH SCHEMABINDING
AS
RETURN
(
SELECT Item = CONVERT(INT, SUBSTRING(#List, Number,
CHARINDEX(#Delimiter, #List + #Delimiter, Number) - Number))
FROM dbo.Numbers
WHERE Number <= CONVERT(INT, LEN(#List))
AND SUBSTRING(#Delimiter + #List, Number, 1) = #Delimiter
);
You can compare the performance to an iterative approach here:
http://sqlfiddle.com/#!3/960d2/1
To avoid the numbers table, you can also try an XML-based version of the function - it is more compact but less efficient:
CREATE FUNCTION [dbo].[SplitInts_XML]
(
#List VARCHAR(MAX),
#Delimiter CHAR(1)
)
RETURNS TABLE
WITH SCHEMABINDING
AS
RETURN ( SELECT Item = CONVERT(INT, Item) FROM (
SELECT Item = x.i.value('(./text())[1]', 'int') FROM (
SELECT [XML] = CONVERT(XML, '<i>' + REPLACE(#List, #Delimiter, '</i><i>')
+ '</i>').query('.') ) AS a CROSS APPLY [XML].nodes('i') AS x(i)) AS y
WHERE Item IS NOT NULL
);
Anyway once you have a function you can simply say:
WHERE ID IN (SELECT Item FROM dbo.SplitInts_Numbers(#MyList, ','));
Passing a string directly into the IN clause is not possible. However, if you are providing the list as a string to a stored procedure, for example, you can use the following dirty method.
First, create this function:
CREATE FUNCTION [dbo].[fnNTextToIntTable] (#Data NTEXT)
RETURNS
#IntTable TABLE ([Value] INT NULL)
AS
BEGIN
DECLARE #Ptr int, #Length int, #v nchar, #vv nvarchar(10)
SELECT #Length = (DATALENGTH(#Data) / 2) + 1, #Ptr = 1
WHILE (#Ptr < #Length)
BEGIN
SET #v = SUBSTRING(#Data, #Ptr, 1)
IF #v = ','
BEGIN
INSERT INTO #IntTable (Value) VALUES (CAST(#vv AS int))
SET #vv = NULL
END
ELSE
BEGIN
SET #vv = ISNULL(#vv, '') + #v
END
SET #Ptr = #Ptr + 1
END
-- If the last number was not followed by a comma, add it to the result set
IF #vv IS NOT NULL
INSERT INTO #IntTable (Value) VALUES (CAST(#vv AS int))
RETURN
END
(Note: this is not my original code, but thanks to versioning systems here at my place of work, I have lost the header comment linking to the source.)
Then use it like so:
SELECT *
FROM tblMyTable
INNER JOIN fnNTextToIntTable(#MyList) AS List ON tblMyTable.ID = List.Value
Or, as in your question:
SELECT *
FROM tblMyTable
WHERE ID IN ( SELECT Value FROM fnNTextToIntTable(#MyList) )
I have 2 string in input for example '1,5,6' and '2,89,9' with same number of element (3 or plus).
Those 2 string i want made a "ordinate join" as
1 2
5 89
6 9
i have think to assign a rownumber and made a join between 2 result set as
SELECT a.item, b.item FROM
(
SELECT
ROW_NUMBER() OVER (ORDER BY (SELECT 0)) AS rownumber,
* FROM dbo.Split('1,5,6',',')
) AS a
INNER JOIN
(
SELECT
ROW_NUMBER() OVER (ORDER BY (SELECT 0)) AS rownumber,
* FROM dbo.Split('2,89,9',',')
) AS b ON a.rownumber = b.rownumber
is that a best practice ever?
When dbo.Split() returns the data-set, nothing you do can assign the row_number you want (based on their order in the string) with absolute certainty. SQL never guarantees an ordering without an ORDER BY that actually relates to the data.
With you trick of using (SELECT 0) to order by you may often get the right values. Probably very often. But this is never guaranteed. Once in a while you will get the wrong order.
Your best option is to recode dbo.Split() to assign a row_number as the string is parsed. Only then can you know with 100% certainty that the row_number really does correspond to the item's position in the list.
Then you join them as you suggest, and get the results you want.
Other than that, the idea does seem fine to me. Though you may wish to consider a FULL OUTER JOIN if one list can be longer than the other.
You can do it like this as well
Consider your split function like this:
CREATE FUNCTION Split
(
#delimited nvarchar(max),
#delimiter nvarchar(100)
) RETURNS #t TABLE
(
id int identity(1,1),
val nvarchar(max)
)
AS
BEGIN
declare #xml xml
set #xml = N'<root><r>' + replace(#delimited,#delimiter,'</r><r>') + '</r></root>'
insert into #t(val)
select
r.value('.','varchar(5)') as item
from #xml.nodes('//root/r') as records(r)
RETURN
END
GO
The it will be a simple task to JOIN them together. Like this:
SELECT
*
FROM
dbo.Split('1,5,6',',') AS a
JOIN dbo.Split('2,89,9',',') AS b
ON a.id=b.id
The upside of this is that you do not need any ROW_NUMBER() OVER(ORDER BY SELECT 0)
Edit
As in the comment the performance is better with a recursive split function. So maybe something like this:
CREATE FUNCTION dbo.Split (#s varchar(512),#sep char(1))
RETURNS table
AS
RETURN (
WITH Pieces(pn, start, stop) AS (
SELECT 1, 1, CHARINDEX(#sep, #s)
UNION ALL
SELECT pn + 1, stop + 1, CHARINDEX(#sep, #s, stop + 1)
FROM Pieces
WHERE stop > 0
)
SELECT pn,
SUBSTRING(#s, start, CASE WHEN stop > 0 THEN stop-start ELSE 512 END) AS s
FROM Pieces
)
GO
And then the select is like this:
SELECT
*
FROM
dbo.Split('1,5,6',',') AS a
JOIN dbo.Split('2,89,9',',') AS b
ON a.pn=b.pn
Thanks to Arion's suggestion. It's very useful for me. I modified the function a little bit to support varchar(max) type of input string, and max length of 1000 for the delimiter string. Also, added a parameter to indicate if you need the empty string in the final return.
For MatBailie's question, because this is an inline function, you can include the pn column in you outer query which is calling this function.
CREATE FUNCTION dbo.Split (#s nvarchar(max),#sep nvarchar(1000), #IncludeEmpty bit)
RETURNS table
AS
RETURN (
WITH Pieces(pn, start, stop) AS (
SELECT convert(bigint, 1) , convert(bigint, 1), convert(bigint,CHARINDEX(#sep, #s))
UNION ALL
SELECT pn + 1, stop + LEN(#sep), CHARINDEX(#sep, #s, stop + LEN(#sep))
FROM Pieces
WHERE stop > 0
)
SELECT pn,
SUBSTRING(#s, start, CASE WHEN stop > 0 THEN stop-start ELSE LEN(#s) END) AS s
FROM Pieces
where start< CASE WHEN stop > 0 THEN stop ELSE LEN(#s) END + #IncludeEmpty
)
But I ran into a bit issue with this function when the list intended to return had more than 100 records. So, I created another function purely using string parsing functions:
Create function [dbo].[udf_split] (
#ListString nvarchar(max),
#Delimiter nvarchar(1000),
#IncludeEmpty bit)
Returns #ListTable TABLE (ID int, ListValue varchar(max))
AS
BEGIN
Declare #CurrentPosition int, #NextPosition int, #Item nvarchar(max), #ID int
Select #ID = 1,
#ListString = #Delimiter+ #ListString + #Delimiter,
#CurrentPosition = 1+LEN(#Delimiter)
Select #NextPosition = Charindex(#Delimiter, #ListString, #CurrentPosition)
While #NextPosition > 0 Begin
Select #Item = Substring(#ListString, #CurrentPosition, #NextPosition-#CurrentPosition)
If #IncludeEmpty=1 or Len(LTrim(RTrim(#Item)))>0 Begin
Insert Into #ListTable (ID, ListValue) Values (#ID, LTrim(RTrim(#Item)))
Set #ID = #ID+1
End
Select #CurrentPosition = #NextPosition+LEN(#Delimiter),
#NextPosition = Charindex(#Delimiter, #ListString, #CurrentPosition)
End
RETURN
END
Hope this could help.
I have the following UDF.
CREATE FUNCTION [dbo].[udf_GenerateVarcharTableFromStringList]
(#list varchar(MAX),
#delimiter char(1) = N',')
RETURNS #tbl TABLE ([Value] varchar(200))
WITH SCHEMABINDING
AS
BEGIN
DECLARE #chrind INT
DECLARE #Piece nvarchar(4000)
SELECT #chrind = 1
WHILE #chrind > 0
BEGIN
SELECT #chrind = CHARINDEX(#delimiter,#list)
IF #chrind > 0
SELECT #Piece = LEFT(#list,#chrind - 1)
ELSE
SELECT #Piece = #list
INSERT #tbl([Value]) VALUES(#Piece)
SELECT #list = RIGHT(#list,LEN(#list) - #chrind)
IF LEN(#list) = 0 BREAK
END
RETURN
END
I call this function with the following code example from a where clause in my sprocs:
WHERE u.[Owner] IN
(SELECT [VALUE]
FROM dbo.udf_GenerateVarcharTableFromStringList(#Owners, ','))
I use this where statement in sprocs that I use for reporting services multivalue parameters. When a user selects just blank for the value it returns the correct data but if a user selects a blank value and another value that actually has text it does not return the blank value owners anymore, just the owners from the text? Any ideas? I take it something is wrong with the function?
Well, from what I could gather from your comments it seems that you need a new splitting function. Here's what I use:
create FUNCTION [dbo].[fnSplitString] (#s varchar(512),#sep char(1))
RETURNS table
AS
RETURN (
WITH Pieces(pn, start, stop) AS (
SELECT 1, 1, CHARINDEX(#sep, #s)
UNION ALL
SELECT pn + 1, stop + 1, CHARINDEX(#sep, #s, stop + 1)
FROM Pieces
WHERE stop > 0
)
SELECT pn,
SUBSTRING(#s, start, CASE WHEN stop > 0 THEN stop-start ELSE 512 END) AS s
FROM Pieces
)
It has a nice enumeration feature to it and it doesn't eat blanks. :)