题解 | #查找山东大学或者性别为男生的信息#

select device_id,gender,age,gpa
from user_profile
where university = '山东大学' 
union all
select device_id,gender,age,gpa
from user_profile
where gender = 'male'

# select device_id,gender,age,gpa

# from user_profile

# where university = '山东大学' or gender = 'male

由于是分别查看，不去重，所以or不行，union也不行，要union all