can you show me a list of allergies?
select allergy from allergy_type
can you show me a list of allergy name?
select allergy from allergy_type
what is their allergy types?
select distinct allergytype from allergy_type
how many students have a food allergy?
select count ( * ) from has_allergy as t1 join allergy_type as t2 on t1.allergy = t2.allergy where t2.allergytype = "food"