Query to select values that match multiple ranges

Question

Hi,
Oracle 10g.
I have a table POINTS(ID INTEGER, CLASS VARCHAR2(15), CUMUL NUMBER(2,1), ...).
In my application (APEX application), I show a list of point classes, order by cumul.
SELECT CLASS FROM POINTS ORDER BY CUMUL;Then user can choose some range of point classes (CUMUL is not shown in the application, it is just for the example) :
CUMUL     CLASS
12.2     31458     <- 
13.4     5S84     <-     range 1 
13.6     78PPH     <- 
15.0     3R594     <- 
15.1     ZB452 
15.5     54IO 
17.6     21GFD 
19.2     A54VV     <- 
19.9     IC112     <-     range 2 
20.8     158RC9     <- 
21.3     G4G5 
23.0     V22     <-     range 3For each range, I store only first and last classes selected by a user, in a table USER_SELECTION(ID, ID_USER, FROM_CLASS, TO_CLASS), so using the example above it would give :
ID     ID_USER          FROM_CLASS     TO_CLASS 
1     12          31458          3R594 
2     12          A54VV          158RC9 
3     12          V22          V22
...     ...          ...          ...The problem is that in a query, I need to return all points selected by a user, and I really don't know how to achieve that without too much work... :
SELECT *
FROM POINTS
WHERE USER_ID=12
AND CLASS IN ( *???* );
Any help would be much appreciated.
Yann.

Answer 1

It's not exactly clear what data is in what tables etc. but perhaps something like this...
select user_selection.id, points.*
from points, user_selection
where user_selection.user_id = 12
and   points.cumul between
      (select cumul from points where class = user_selection.class1)
      and
      (select cumul from points where class = user_selection.class2)
order by user_select.id, points.cumul