SQL Server - find nth occurrence in a string

Solution 1:

One way (2k8);

select 'abc_1_2_3_4.gif  ' as img into #T
insert #T values ('zzz_12_3_3_45.gif')

;with T as (
    select 0 as row, charindex('_', img) pos, img from #T
    union all
    select pos + 1, charindex('_', img, pos + 1), img
    from T
    where pos > 0
)
select 
    img, pos 
from T 
where pos > 0   
order by img, pos

>>>>

img                 pos
abc_1_2_3_4.gif     4
abc_1_2_3_4.gif     6
abc_1_2_3_4.gif     8
abc_1_2_3_4.gif     10
zzz_12_3_3_45.gif   4
zzz_12_3_3_45.gif   7
zzz_12_3_3_45.gif   9
zzz_12_3_3_45.gif   11

Update

;with T(img, starts, pos) as (
    select img, 1, charindex('_', img) from #t
    union all
    select img, pos + 1, charindex('_', img, pos + 1)
    from t
    where pos > 0
)
select 
    *, substring(img, starts, case when pos > 0 then pos - starts else len(img) end) token
from T
order by img, starts

>>>

img                 starts  pos     token
abc_1_2_3_4.gif     1       4       abc
abc_1_2_3_4.gif     5       6       1
abc_1_2_3_4.gif     7       8       2
abc_1_2_3_4.gif     9       10      3
abc_1_2_3_4.gif     11      0       4.gif  
zzz_12_3_3_45.gif   1       4       zzz
zzz_12_3_3_45.gif   5       7       12
zzz_12_3_3_45.gif   8       9       3
zzz_12_3_3_45.gif   10      11      3
zzz_12_3_3_45.gif   12      0       45.gif

Solution 2:

You can use the same function inside for the position +1

charindex('_', [TEXT], (charindex('_', [TEXT], 1))+1)

in where +1 is the nth time you will want to find.

Solution 3:

You can use the CHARINDEX and specify the starting location:

DECLARE @x VARCHAR(32) = 'MS-SQL-Server';

SELECT 
  STUFF(STUFF(@x,3 , 0, '/'), 8, 0, '/') InsertString
  ,CHARINDEX('-',LTRIM(RTRIM(@x))) FirstIndexOf
  ,CHARINDEX('-',LTRIM(RTRIM(@x)), (CHARINDEX('-', LTRIM(RTRIM(@x)) )+1)) SecondIndexOf
  ,CHARINDEX('-',@x,CHARINDEX('-',@x, (CHARINDEX('-',@x)+1))+1) ThirdIndexOf
  ,CHARINDEX('-',REVERSE(LTRIM(RTRIM(@x)))) LastIndexOf;
GO

Solution 4:

You can use the following function to split the values by a delimiter. It'll return a table and to find the nth occurrence just make a select on it! Or change it a little for it to return what you need instead of the table.

CREATE FUNCTION dbo.Split
(
    @RowData nvarchar(2000),
    @SplitOn nvarchar(5)
)  
RETURNS @RtnValue table 
(
    Id int identity(1,1),
    Data nvarchar(100)
) 
AS  
BEGIN 
    Declare @Cnt int
    Set @Cnt = 1

    While (Charindex(@SplitOn,@RowData)>0)
    Begin
        Insert Into @RtnValue (data)
        Select 
            Data = ltrim(rtrim(Substring(@RowData,1,Charindex(@SplitOn,@RowData)-1)))

        Set @RowData = Substring(@RowData,Charindex(@SplitOn,@RowData)+1,len(@RowData))
        Set @Cnt = @Cnt + 1
    End

    Insert Into @RtnValue (data)
    Select Data = ltrim(rtrim(@RowData))

    Return
END

Solution 5:

DECLARE @str AS VARCHAR(100)
SET @str='1,2  , 3,   4,   5,6'
SELECT COALESCE(LTRIM(CAST(('<X>'+REPLACE(@str,',' ,'</X><X>')+'</X>') AS XML).value('(/X)[1]', 'varchar(128)')), ''),
       COALESCE(LTRIM(CAST(('<X>'+REPLACE(@str,',' ,'</X><X>')+'</X>') AS XML).value('(/X)[2]', 'varchar(128)')), ''),
       COALESCE(LTRIM(CAST(('<X>'+REPLACE(@str,',' ,'</X><X>')+'</X>') AS XML).value('(/X)[3]', 'varchar(128)')), ''),
       COALESCE(LTRIM(CAST(('<X>'+REPLACE(@str,',' ,'</X><X>')+'</X>') AS XML).value('(/X)[4]', 'varchar(128)')), ''),
       COALESCE(LTRIM(CAST(('<X>'+REPLACE(@str,',' ,'</X><X>')+'</X>') AS XML).value('(/X)[5]', 'varchar(128)')), ''),
       COALESCE(LTRIM(CAST(('<X>'+REPLACE(@str,',' ,'</X><X>')+'</X>') AS XML).value('(/X)[6]', 'varchar(128)')), ''),
       COALESCE(LTRIM(CAST(('<X>'+REPLACE(@str,',' ,'</X><X>')+'</X>') AS XML).value('(/X)[7]', 'varchar(128)')), ''),
       COALESCE(LTRIM(CAST(('<X>'+REPLACE(@str,',' ,'</X><X>')+'</X>') AS XML).value('(/X)[8]', 'varchar(128)')), ''),
       COALESCE(LTRIM(CAST(('<X>'+REPLACE(@str,',' ,'</X><X>')+'</X>') AS XML).value('(/X)[9]', 'varchar(128)')), '')