Rock, Paper, Scissors query?

Question

Hi there, I have a "limiting" question I'm hoping someone can help me out with.
I work for a hospital on the employee's database. I'm trying to update a column in the employee demographic table called "workgroup". It's never been used before so currently the column sits empty.
I need to place one of 3 different codes in that column based on the level of patient contact the employee has. D = Direct contact, I = Indirect contact and N = No contact.
I will need to base this off of another table called Exposures. It's a table that tracks the level of exposure the employee is subjected to. So ER nurses would be Level 1, but the cleaning crew are Level 3.
Here's my problem, unfortunately due to poor past practices, many people are in more than one Level. For example, most nurses are in both Level 1 and Level 2. The reason for this... I have no idea.
So my question is, how if say Sara Johnson was in Level 1 and Level 2, would I place a "D" in her workgroup column and that's it. I've built a script with a CASE statement but that doesn't give me what I want. I gives her both a "D" and an "I". But the "D" is more important - it trumps the "I". Get it? Basically it's like rock paper scissors.

Answer 1

MIN worked great!! Thanks a lot!! I think this just saved us a lot of manual excel work.
Here's the script: (sorry about the formatting)
SELECT     E.ID, E.LNAME, E.FNAME, NVL(E.MI,' ') MI, E.BDATE,
     MIN(B.CODE) CODE, MIN(B.WKGP) WKGP,
     L.DESCR
FROM     EMPLOYEE E, LOC L,     (SELECT     EMPLOYEE EE, EXPOSURE CODE,
                         CASE      WHEN EXPOSURE = 'Level 1' THEN 'D'
                              WHEN FLDEXPOSURE = 'Level 2' THEN 'I'
                              WHEN FLDEXPOSURE = 'Level 3' THEN 'N'
                              ELSE     ' '
                         END WKGP
                    FROM     EXPHIST
                    WHERE     FLDEXPOSURE IN ('Level 1','Level 2','Level 3')) B
WHERE     E.LOC = L.CODE          AND
     L.CODE = 'South'      AND
     E.STATUS IN     (SELECT CODE
               FROM     EMPSTATS
               WHERE     ACTIVE <> 'n')     AND
     E.REC_NUM = B.EE
GROUP BY E.ID, E.LNAME, E.FNAME, E.MI, E.BDATE,
     L.DESCR
ORDER BY E.LNAME, E.FNAME