Query with LISTAGG() string function does not return the desired output

oracle-11gstring-aggregationwindow functions

I'm new to ORACLE and I'm trying to use a string aggregation function in my query to concatenate the value of rows with a comma ,

this is the structure of my tables:

  1. Student(STUDENT_ID,student_name,age)
  2. Course(course_no,description)
  3. Student_Course(student_id,course_id,nomreh)

description column indicates the name of the course for example Algebra or Math. Nomreh column shows the Mark each student achieved in each course (it's a Persian word).

This is my query

Select s.student_name , 
   LISTAGG(c.description, ',') WITHIN GROUP (ORDER BY c.description) AS 
   LISTAGG(sc.nomreh, ',') WITHIN GROUP (ORDER BY sc.nomreh) AS Ranks
from student s inner join 
        student_course sc on s.student_id = sc.student_id 
           inner join
        course c on sc.course_id = c.course_no
 group by s.student_name 

I want the output to show:

[Student-name]   [Course-Description]    [Nomre]
  Artin           Algebra,Math,Sport    10,11,12

each value in [Nomreh] column should be exactly for that [Course] column and for that specific student . Unfortunately my query does not give the desired output and the values in Nomreh column are not in correct order with [Course-Description] column.

Best Answer

Change this part of your query to the below:

       LISTAGG(c.description, ',') WITHIN GROUP (ORDER BY 
                s.student_name,c.description,sc.nomreh) AS Courses,
       LISTAGG(sc.nomreh, ',') WITHIN GROUP (ORDER BY 
                s.student_name,c.description,sc.nomreh) AS Ranks