Indicate the full name of the patients who have 3 different allergies.
full name refers to first, last; have 3 different allergies refer to allergies where COUNT(DESCRIPTION) > 3;
SELECT T1.first, T1.last FROM patients AS T1 INNER JOIN allergies AS T2 ON T1.patient = T2.PATIENT GROUP BY T1.patient ORDER BY COUNT(DISTINCT T2.DESCRIPTION) > 3