SELECT count(*) ,  avg(age) ,  city_code FROM student WHERE sex  =  'M' GROUP BY city_code
Find the average age and number of male students (with sex M) from each city.
SELECT count ( * ) , avg ( age ) , city_code FROM student WHERE sex = 'M ' GROUP BY city_code
select count ( * ) , avg ( age ) , city_code from student where sex = value group by city_code
Find the average age and number of male students ( with sex M ) from each city .