DECLARE @counter int = 1;
DECLARE @colString varchar(10) = 'AA%#&    ';

WHILE @counter <= DATALENGTH(@colString)
   BEGIN
   SELECT CHAR(ASCII(SUBSTRING(@colString, @counter, 1))) as [Character],
   ASCII(SUBSTRING(@colString, @counter, 1)) as [ASCIIValue]
     
   SET @counter = @counter + 1
   END
GO

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