SQL concatenate strings

Question

im working in sql server 2008, i want to concatenate two strings, and the condition is

@str1 = 'A1,B1,C1'
@str2 = 'A2,B2,C2'

i want the result as

@result = 'A1,A2,B1,B2,C1,C2'

Please help...

Answer 1

First create a split function to get you items seperately:

CREATE FUNCTION [dbo].[Split]
(
    @String NVARCHAR(4000),
    @Delimiter NCHAR(1)
)
RETURNS TABLE
AS
RETURN
(
    WITH Split(stpos,endpos)
    AS(
        SELECT 0 AS stpos, CHARINDEX(@Delimiter,@String) AS endpos
        UNION ALL
        SELECT endpos+1, CHARINDEX(@Delimiter,@String,endpos+1)
            FROM Split
            WHERE endpos > 0
    )
    SELECT 'Id' = ROW_NUMBER() OVER (ORDER BY (SELECT 1)),
        'Data' = SUBSTRING(@String,stpos,COALESCE(NULLIF(endpos,0),LEN(@String)+1)-stpos)
    FROM Split
)
GO

Now you can first split then and order your result and then concat the values

DECLARE @DelimitedString NVARCHAR(128)
SET @DelimitedString =  @str1 + ',' + @str2
SELECT @result = COALESCE(@result + ',', '') +Data
  FROM (SELECT Data 
          FROM dbo.Split(@DelimitedString, ',')
      ORDER BY Data)

Answer 2

The way you are storing your data is really bad practice. However here is a solution for training purposes:

DECLARE 
   @str1 varchar(30) = 'A1,B1,C1',
   @str2 varchar(30) = 'A2,B2,C2',
   @result varchar(60)

;WITH split as
(
  SELECT t.c.value('.', 'VARCHAR(2000)') x
  FROM (
      SELECT x = CAST('<t>' + 
          REPLACE(@str1 + ',' + @str2, ',', '</t><t>') + '</t>' AS XML)
  ) a
CROSS APPLY x.nodes('/t') t(c)
)
SELECT
  @result =
    STUFF(( 
        SELECT ',' + x
        FROM split
        ORDER BY x
        for xml path(''), type 
          ).value('.', 'varchar(max)'), 1, 1, '')

SELECT @result

Result:

A1,A2,B1,B2,C1,C2

Answer 3

SET @result = @str1 + ',' + @str2
SELECT @result

UPDATE 1

I think the best approach will be to, first get full string and then splitting it with comma, and then storing that in a temp table and then sorting, might be a good idea.

CREATE FUNCTION SplitString
(    
      @Input NVARCHAR(MAX),
      @Character CHAR(1)
)
RETURNS @Output TABLE (
      Item NVARCHAR(1000)
)
AS
BEGIN
      DECLARE @StartIndex INT, @EndIndex INT

      SET @StartIndex = 1
      IF SUBSTRING(@Input, LEN(@Input) - 1, LEN(@Input)) <> @Character
      BEGIN
            SET @Input = @Input + @Character
      END

      WHILE CHARINDEX(@Character, @Input) > 0
      BEGIN
            SET @EndIndex = CHARINDEX(@Character, @Input)

            INSERT INTO @Output(Item)
            SELECT SUBSTRING(@Input, @StartIndex, @EndIndex - 1)

            SET @Input = SUBSTRING(@Input, @EndIndex + 1, LEN(@Input))
      END

      RETURN
END
GO


SELECT Item FROM 
dbo.SplitString(@result,',') ORDER BY Item

Answer 4

Try:

SELECT stuff((SELECT ',' + T.str FROM
(SELECT 
    PARSENAME(REPLACE(@str1,',','.'),1) str UNION ALL
    PARSENAME(REPLACE(@str1,',','.'),2) str UNION ALL
    PARSENAME(REPLACE(@str1,',','.'),3) str UNION ALL
    PARSENAME(REPLACE(@str2,',','.'),1) str UNION ALL
    PARSENAME(REPLACE(@str2,',','.'),2) str UNION ALL
    PARSENAME(REPLACE(@str2,',','.'),3) str )T
    ORDER BY T.str
FOR XML PATH('')),1,1,'')