Join tables with aggregate function

Question

Hello
I have 4 views that I need to perform aggregate function, count, on and then join them for query output.
Basically each view has a column with a score and a subcontractor name. One subcontractor may have more than one score in each view.
Here is the sql that I'm working with thus far:
select e.sub_name, (count(e.score) - 1), (count(v.score) - 1), (count(s.score) - 1), (count(u.score) - 1)
from speed.v_ratings_ex e, speed.v_ratings_vg v, speed.v_ratings_sat s, speed.v_ratings_uns u
where v.sub_name = e.sub_name
and s.sub_name = e.sub_name
and u.sub_name = e.sub_name
group by e.sub_name
order by e.sub_name asc;
This results in each column returning the same value b/c the join is performed before the aggregate function.
Can anyone offer some help so that I may get the desired results?

Answer 1

You need to use in-line views to perform the aggregates, then join the in-line views.
Something like:
SELECT e.sub_name, e.score - 1 escore, v.score - 1 vscore,
       s.score - 1 sscore, u.score - 1 uscore
FROM (SELECT sub_name,count(*) score
      FROM v_ratings_ex
      GROUP BY sub_name) e,
     (SELECT sub_name,count(*) score
      FROM v_ratings_vg
      GROUP BY sub_name) v,
     (SELECT sub_name,count(*) score
      FROM v_ratings_sat
      GROUP BY sub_name) s,
     (SELECT sub_name,count(*) score
      FROM v_ratings_uns
      GROUP BY sub_name) u
WHERE v.sub_name = e.sub_name and
      s.sub_name = e.sub_name and
      u.sub_name = e.sub_name
ORDER BY e.sub_name asc;TTFn
John