Find the first name and gender of student who have more than one pet.
create table student (fname varchar, sex varchar, stuid varchar, PRIMARY KEY (fname)); create table has_pet (stuid varchar, PRIMARY KEY (stuid))
select t1.fname, t1.sex from student as t1 join has_pet as t2 on t1.stuid = t2.stuid group by t1.stuid having count(*) > 1