From http://www.aspsnippets.com/Articles/Split-function-in-SQL-Server-Example-Function-to-Split-Comma-separated-Delimited-string-in-SQL-Server-2005-2008-and-2012.aspx

fn_SplitString.sql

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