Database: cre_Students_Information_Systems
Question: What is the least common detention type? Show the type code and the description.
SQL:
SELECT T1.detention_type_code ,  T2.detention_type_description FROM Detention AS T1 JOIN Ref_Detention_Type AS T2 ON T1.detention_type_code  =  T2.detention_type_code GROUP BY T1.detention_type_code ORDER BY count(*) ASC LIMIT 1