I am trying to select the string between every pair <....> in the fifth column "QuestionTags".
here is a sample of the data:
i used CHARINDEX function but it returned me an integer.
i also used SUBSTRING but it asks me to define the character index and length of string.
Any suggestions?
If you can use SQL Server 2016 for this then there is a built in string_split function that will do the job
SELECT *
FROM YourTable
OUTER APPLY (SELECT SUBSTRING(value, 2, 8000) value
FROM string_split(QuestionTags, '>')
WHERE value <> '') OA
A demo in Stack Exchange Data Explorer as it looks like you are using SE data.
SUBSTRING() here instead of STUFF()?
If you are open to a Table-Valued-Function and not using 2016.
Tired of extracting strings (charindex,left,right,substring,...), I modified a Parse/Split function to accept two NON-LIKE delimiters. In your case a < and >
Example
Declare @YourTable table (ID int,QuestionTags varchar(max))
Insert Into @YourTable values
(1,'<php><arrays><cloud><tag-cloud>')
,(2,'<windows><mailto>')
Select A.ID
,B.*
From @YourTable A
Cross Apply [dbo].[udf-Str-Extract](A.QuestionTags,'<','>') B
Returns
ID RetSeq RetPos RetVal
1 1 2 php
1 2 7 arrays
1 3 15 cloud
1 4 22 tag-cloud
2 1 2 windows --<< Second Record
2 2 11 mailto
The UDF if interested
CREATE FUNCTION [dbo].[udf-Str-Extract] (@String varchar(max),@Delimiter1 varchar(100),@Delimiter2 varchar(100))
Returns Table
As
Return (
with cte1(N) As (Select 1 From (Values(1),(1),(1),(1),(1),(1),(1),(1),(1),(1)) N(N)),
cte2(N) As (Select Top (IsNull(DataLength(@String),0)) Row_Number() over (Order By (Select NULL)) From (Select N=1 From cte1 N1,cte1 N2,cte1 N3,cte1 N4,cte1 N5,cte1 N6) A ),
cte3(N) As (Select 1 Union All Select t.N+DataLength(@Delimiter1) From cte2 t Where Substring(@String,t.N,DataLength(@Delimiter1)) = @Delimiter1),
cte4(N,L) As (Select S.N,IsNull(NullIf(CharIndex(@Delimiter1,@String,s.N),0)-S.N,8000) From cte3 S)
Select RetSeq = Row_Number() over (Order By N)
,RetPos = N
,RetVal = left(RetVal,charindex(@Delimiter2,RetVal)-1)
From (
Select *,RetVal = Substring(@String, N, L)
From cte4
) A
Where charindex(@Delimiter2,RetVal)>1
)
/*
Max Length of String 1MM characters
Declare @String varchar(max) = 'Dear [[FirstName]] [[LastName]], ...'
Select * From [dbo].[udf-Str-Extract] (@String,'[[',']]')
*/
