SQL query for students mark functionality in SQL server [closed] - sql-server

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There are 3 tables
Students(student_id, st_name)
Subjects(subject_id,sub_name)
Marks(st_id,sub_id,Score)
Write an SQL query to display the student name, average score of the student, maximum mark obtained by the student , name of the subject in which the student has scored maximum marks.
Below is the code I wrote
I am getting the errors -Column 'students.name' and 'subjects.name' are invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause.
select students.st_name as Students_Name,avg(Score) as Average, max(Score) as Maximum,subjects.sub_name as Max_Subject_name
from marks
join students on students.student_id=marks.st_id
join subjects on subjects.subject_id=marks.sub_id
join
(
select st_id,avg(score) as Average,max(score) as Maximum from marks group by st_id
) as x on x.st_id=marks.st_id
order by students.st_name,subjects.sub_name;

Answer 1

Try this
;with cte as
(
select students.st_name as Students_Name
,students.student_id
,RANK() over(partition by students.student_id order by marks.score desc) as seq
,subjects.sub_name as Max_Subject_name
,Marks.Score
from marks
INNER join students
on students.student_id=marks.st_id
INNER join subjects
on subjects.subject_id=marks.sub_id
)
select
Students_Name
,student_id
,Max_Subject_name
,Score
,(select avg(score) from cte b where b.student_id=a.student_id) as average
from cte a
where seq=1

Answer 2

Try
select students.name as Students_Name
,avg(Score) as Average
,max(Score) as Maximum
,subjects.name as Max_Subject_name
from marks
INNER join students
on students.student_id=marks.st_id
INNER join subjects
on subjects.subject_id=marks.st_id
GROUP BY students.name
,subjects.name
order by students.name
,subjects.name;
or if you want your query:
select students.name as Students_Name,x.Average, x.Maximum,subjects.name as Max_Subject_name
from marks
join students on students.student_id=marks.st_id
join subjects on subjects.subject_id=marks.st_id
join
(
select st_id,avg(score) as Average,max(score) as Maximum from marks group by st_id
) as x on x.st_id=marks.st_id
order by students.name,subjects.name;