Creating Non-Repeating fields

Question

Hello all,
I am creating a query that lists a bunch of student ID's and their schedules. However, the ID's of students should only show on the first row of thier schedule. I've figured out a way to do it with the Lag function, but I was wondering if there is a better way or if this is the only way? Also, does this "method" have a name?
For example, instead of:
Student ID    Course
  3823481     Math 101
  3823481     English 201
  3823481     History 230
  5293012     Art 402
  5293012     English 301
  5293012     CGT 212I want this to show:
Student ID    Course
  3823481     Math 101
              English 201
              History 230
  5293012     Art 402
              English 301
              CGT 212This is kind of what my code looks like:
  -- Non-repeating PNumber
       Case Lag (ID) over (order by ID)
         When ID Then ' '
         Else ID
        End as Student_ID,
  -- List Classes
       Course_Title
  From (...)
  Where (...)

Answer 1

Hi ..
a possible solution:
with q as(
select 3823481 Student_ID ,'Math 101' Course from dual union all
select 3823481    ,'English 201' from dual union all
select 3823481     ,'History 230' from dual union all
select 5293012     ,'Art 402' from dual union all
select 5293012    ,'English 301' from dual union all
select 5293012    ,'CGT 212' from dual)
select decode(row_number() over (partition by Student_ID order by course),1,Student_ID) Student_ID,course from q