Max Date function by Group is not catching a Null Date

Question

I have a query that returns the MAX CLINICALDATE. It is worknig great except if their is no CLINCIALDATE then it doesn't bring that group back and it needs to. Thank you for your help.
SELECT PERSON.MEDRECNO, MEDICATE.INSTRUCTIONS, PERSON.LASTNAME, PERSON.FIRSTNAME, MEDICATE.STARTDATE, MEDICATE.STOPDATE, MEDICATE.STOPREASON, MEDICATE.DESCRIPTION, PRESCRIB.REFILLS, PRESCRIB.QUANTITY, PRESCRIB.CLINICALDATE
FROM
     ((ML.MEDICATE MEDICATE
INNER JOIN ML.PERSON PERSON ON (MEDICATE.PID = PERSON.PID))
     LEFT OUTER JOIN ML.PRESCRIB PRESCRIB ON (MEDICATE.PID = PRESCRIB.PID)     AND (MEDICATE.MID = PRESCRIB.MID))
     LEFT OUTER JOIN ML.USRINFO USRINFO ON (PRESCRIB.PVID = USRINFO.PVID)
WHERE PERSON.MEDRECNO='20-14-38' AND (MID, CLINICALDATE) IN
(SELECT MID, MAX(CLINICALDATE) FROM PRESCRIB GROUP BY MID) and (STOPREASON is null or STOPREASON = ' ') and (MEDICATE.STOPDATE = to_date('4700-12-31 00:00:00', 'yyyy/mm/dd hh24:mi:ss'))
ORDER BY MEDICATE.DESCRIPTION

Answer 1

As stated when entering the forum, SQL Developer is a tool; you want the SQL And PL/SQL forum instead.
Regards,
K.