Fabio,

For some reason I can not make it to work. I'm now trying a simpler query

SELECT VISITS.patient_name, VISITS.visit_date, Doctors.doctor_Specialty
FROM Visits INNER JOIN Doctors ON Visits.Doctor_Name = Doctors.Doctor_Name
GROUP BY Patient_Name, Visit_Date, Doctor_Specialty
HAVING (count(DISTINCT Doctors.Doctor_Name) >1 AND count(DISTINCT Doctors.Doctor_Specialty)=1);

but I'm getting missing operator at the expression in Having clause.

Looks like it doesn't take the DISTINCT keyword. The above query works without DISTINCT, but returns 0 rows.