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题解 | 用where过滤空值练习

select device_id, gender, age, university from user_profile where age is not NULL

2025-05-15

0 24

题解 | 查找除复旦大学的用户信息

select device_id, gender, age, university from user_profile where university not in ("复旦大学")

2025-05-15

0 21