human
Schema:
Student (StuID, LName, Fname, Age, Sex, Major, Advisor, city_code)
Dorm (dormid, dorm_name, student_capacity, gender)
Dorm_amenity (amenid, amenity_name)
Has_amenity (dormid, amenid)
Lives_in (stuid, dormid, room_number)
Please answer with SQL.
assistant
Sure, I understand.
human
Find the number of students whose age is older than the average age for each gender.
assistant
SELECT count(*) , sex FROM student WHERE age > (SELECT avg(age) FROM student) GROUP BY sex
human
Find the first and last name of students whose age is younger than the average age.
assistant
SELECT fname , lname FROM student WHERE age < (SELECT avg(age) FROM student)
human
Find the average age of students living in each dorm and the name of dorm.
assistant
SELECT avg(T1.age) , T3.dorm_name FROM student AS T1 JOIN lives_in AS T2 ON T1.stuid = T2.stuid JOIN dorm AS T3 ON T3.dormid = T2.dormid GROUP BY T3.dorm_name
human
Find the average age and number of male students (with sex M) from each city.
assistant
SELECT count(*) , avg(age) , city_code FROM student WHERE sex = 'M' GROUP BY city_code
human
Find the average age of all students living in the each city.
assistant
SELECT avg(age) , city_code FROM student GROUP BY city_code
human
Find the number and average age of students living in each city.
assistant
SELECT COUNT( * ) , avg ( age ) , city_code FROM student GROUP BY city_code ;