SQL Server 2005 - Remove repeating spaces from string using CTE

This function removes repeating spaces from a string using a recursive function, leaving only one space between words.

Code:

---

-- =============================================
-- Author:                <Michael Ciurescu>
-- Create date: <2011-12-27>
-- Description:        <Removes repeating spaces from a string>
-- =============================================
CREATE FUNCTION [dbo].[fn_RemoveSpaces](
        @Data VARCHAR(MAX)
)
RETURNS VARCHAR(MAX)
AS
BEGIN
        DECLARE @RetStr NVARCHAR(MAX)
       
        -- SELECT dbo.fn_RemoveSpaces(' jlas dflaks djflkj        a;lsdk flask dfla sd      aa    ')
       
        ; WITH aa AS (
                SELECT @Data AS data, CAST(1 AS INT) AS i
               
                UNION ALL
               
                SELECT REPLACE(data, '  ',  ' ') data, i + 1
                FROM aa
                WHERE CHARINDEX('  ', data) > 0
        )
        , bb AS (
                SELECT MAX(i) AS MAX_I FROM aa
        )
        SELECT @RetStr = data
        FROM aa
                INNER JOIN bb ON aa.i = bb.MAX_I
        OPTION (MAXRECURSION 0)
       
        RETURN LTRIM(RTRIM(@RetStr))
END

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