Add quotes around alpha characters in alphanumeric strings using T-SQL?

Question

I want to add quotes around alphabets in an alphanumeric string. For eg: If my string is 8AB8973, the output expected is 8'AB'8973. There is no specific pattern in which the numbers and characters will occur. I tried to run the following piece of code I found on StackOverflow, but it adds a space between numbers and alphabets, when I try to replace the space with quotes, the query takes forever to run.

    DECLARE @position INT;
    DECLARE @string VARCHAR(max);

    SET @string = '9FX8173'

    WHILE 1 = 1
      BEGIN
          SET @position = (SELECT Min(position)
                           FROM   (VALUES (Patindex('%[^ 0-9][0-9]%', @string)),
                                          (Patindex('%[0-9][^ 0-9]%', @string))) AS T(position)
                           WHERE  T.position > 0);

          IF @position IS NULL
            BREAK;

          SET @string = Stuff(@string, @position + 1, 0, ' ');
       END

       PRINT @string

Answer 1

In addition to replacing space with a quote in the STUFF function, you need to do the same in the PATINDEX search expressions:

DECLARE @position INT;
DECLARE @string VARCHAR(max);

SET @string = '9FX8173';

WHILE 1 = 1
BEGIN
    SET @position = (
        SELECT MIN(position)
        FROM (VALUES (PATINDEX('%[^''0-9][0-9]%', @string)),
                     (PATINDEX('%[0-9][^''0-9]%', @string))) AS T(position)
        WHERE  T.position > 0);

    IF @position IS NULL
        BREAK;

    SET @string = STUFF(@string, @position + 1, 0, '''');
END

PRINT @string;