Database: pets_1
Question: Find the first name of students who have cat or dog pet.
SQL: select distinct t1.fname from student as t1 join has_pet as t2 on t1.stuid  =  t2.stuid join pets as t3 on t3.petid  =  t2.petid where t3.pettype  =  'cat' or t3.pettype  =  'dog'