WITH STD AS (SELECT ST.NAME AS STUDENT_NAME, FR.FRIEND_ID AS FRIEND_ID, PA.SALARY AS STUDENT_SALARY FROM STUDENTS ST JOIN FRIENDS FR ON ST.ID = FR.ID JOIN PACKAGES PA ON FR.ID = PA.ID),

FRI AS (SELECT FRR.FRIEND_ID AS FRIEND_ID, PAA.SALARY AS FRIEND_SALARY FROM FRIENDS FRR JOIN PACKAGES PAA ON FRR.FRIEND_ID = PAA.ID)

SELECT S.STUDENT_NAME FROM STD S JOIN FRI F ON S.FRIEND_ID = F.FRIEND_ID WHERE F.FRIEND_SALARY > S.STUDENT_SALARY ORDER BY F.FRIEND_SALARY

with first as ( select s.Name,p.Salary,f.ID,f.Friend_ID from Students s Join Friends f on s.ID=f.ID join Packages p on p.ID=f.ID ), second as (

select p1.Salary as Friends_salary,f1.id from Friends f1 join Packages p1 on f1.Friend_ID=p1.ID)

select first.name from first join second On first.ID=second.id where first.salary

Here's a simple solution in MySQL: Step 1: Calculate the salary of each student Step 2: Calulate the salary of each friend Step 3: Select the students where their salary is less than that of their friend

WITH student_salary AS
(
    SELECT s.ID AS student_id, s.Name AS student_name, p.Salary AS student_salary
    FROM Students s
    LEFT JOIN Packages p
    ON s.ID = p.ID
),
friend_salary AS
(
    SELECT f.Friend_ID AS friend_id, f.ID AS student_id, p.Salary AS friend_salary
    FROM Friends f
    LEFT JOIN Packages p
    ON f.Friend_ID = p.ID
)
SELECT ss.student_name
FROM student_salary ss
LEFT JOIN friend_salary fs
ON ss.student_id = fs.student_id
WHERE ss.student_salary < fs.friend_salary
ORDER BY fs.friend_salary;

with student_salary as ( select s.id as id, s.name as name, sum(p.salary) as salary FROM students s inner join packages p on s.id = p.id group by s.id, s.name ), bestie_salary as ( select f.id as id, f.friend_id as bst_id, sum(p.salary) as salary from friends f inner join packages p on f.friend_id = p.id group by f.id, f.friend_id ), cte as ( select s.id as id, s.name as name, s.salary as student_salary, b.bst_id as friend_id, b.salary as friend_salary from student_salary s inner join bestie_salary b on s.id = b.id ) select name from cte where friend_salary > student_salary order by friend_salary asc

select student_name from (select s.id student_id, s.name student_name, p.salary student_salary,
f.friend_id friend_id, f.friend_name friend_name, f.friend_salary friend_salary from students s join packages p on p.id = s.id join (select ff.id, ff.friend_id, i.name as friend_name, pp.salary as friend_salary from friends ff join packages pp on pp.id = ff.friend_id join students i on i.id = ff.friend_id ) as f on f.id = s.id ) as mains where student_salary < friend_salary order by friend_salary