You are given the following table: attendance(roll_num,class_date,status)
Where the ‘status’ column takes value from the set {‘A’ (Absent)’, ‘P’ (present)} assume that a total of 40 classes are held.
Which the following is the correct output of the following query
SELECT roll_num
FROM attendance as A1
WHERE (SELECT COUNT(status)
FROM attendance as A2
WHERE A1.roll_num = A2.roll_num
AND status = “P”) < 30
1
Roll number of all the students whose attendance is less the 50 % of the class
2
Roll number of all the students whose attendance is more than 75% of the class
3
Roll number of all the students whose attendance is less the 75% of the class
4
Roll number of all the students whose attendance is more the 50 % of the class