题解 | #用where过滤空值练习#
用where过滤空值练习
https://www.nowcoder.com/practice/08c9846a423540319eea4be44e339e35
SELECT device_id,gender,age,university FROM user_profile WHERE age != ''; SELECT device_id,gender,age,university FROM user_profile WHERE age is null;
is null
!= ''
