PARTITION BY ? Return an ID based on the minimum value of another column

Question

Hi guys
I want to return the ID column of a row, where 2 other columns = a set value, and a 3rd column has the minimum value matching the other criteria.
so in effect :
with t as (
select 1 dst_id, 'abc' dst_title, 1 edition_from, 1 media_item from dual
union all
select 2 dst_id, 'abc' dst_title, 1 edition_from, 2 media_item from dual
union all
select 3 dst_id, 'abc' dst_title, 2 edition_from, 1 media_item from dual
union all
select 4 dst_id, 'abc' dst_title, 2 edition_from, 2 media_item from dual
union all
select 5 dst_id, 'def' dst_title, 1 edition_from, 1 media_item from dual
union all
select 6 dst_id, 'def' dst_title, 1 edition_from, 2 media_item from dual
  select dst_id
  from t
  where dst_title = 'abc'
  and edition_from = 1
  and media_item = minimum value of media item using above where clauseWould return dst_id = 1 because it has the minimum media item value of 1 where dst_title = abc and edition_from = 1
Can this be done in 1 query ? I've been trying it using partition by and over dst_title, edition_from but that doesn't work.
I'm currently doing it using a sub query or 2 queries, but thought there must be a way to do it in one ?
Thanks all
Scott

Answer 1

Like this?
SQL> with t as (
  2  select 1 dst_id, 'abc' dst_title, 1 edition_from, 1 media_item from dual
  3  union all
  4  select 2 dst_id, 'abc' dst_title, 1 edition_from, 2 media_item from dual
  5  union all
  6  select 3 dst_id, 'abc' dst_title, 2 edition_from, 1 media_item from dual
  7  union all
  8  select 4 dst_id, 'abc' dst_title, 2 edition_from, 2 media_item from dual
  9  union all
10  select 5 dst_id, 'def' dst_title, 1 edition_from, 1 media_item from dual
11  union all
12  select 6 dst_id, 'def' dst_title, 1 edition_from, 2 media_item from dual
13  )
14  select dst_id
15  from (select t.*
16        ,      row_number() over (partition by dst_title, edition_from order by media_item) rn
17        from   t
18        where  dst_title = 'abc'
19        and    edition_from = 1)
20  where rn = 1;
    DST_ID
         1
SQL>