Require distinct results, but consolidating other details by comma

Question

I have an SQL script which produces distinct results.
The results I get are:
Date_Received Description       Source  Rma
01/02/2006    WIDGET1           Comp1   100000
01/02/2006    WIDGET2           Comp1   100000
01/02/2006    WIDGET3           Comp1   100000
01/02/2006    WIDGET1           Comp1   100001
01/02/2006    WIDGET3           Comp1   100002
01/02/2006    WIDGET8           Comp1   100002
01/02/2006    WIDGET8           Comp2   100003But I want:
Date_Received Description                         Source  Rma
01/02/2006    WIDGET1, WIDGET2, WIDGET3           Comp1   100000
01/02/2006    WIDGET1                             Comp1   100001
01/02/2006    WIDGET3, WIDGET8                    Comp1   100002
01/02/2006    WIDGET8                             Comp2   100003Is this simple to do?
My query, as it is:
select distinct
da Date_Received,
de Description,
so Source,
RMA
from
(select
to_char(rmh.date_entered,'DD/MM/YYYY') Da,
IFSAPP.SALES_PART_API.Get_Catalog_Desc(rml.contract,rml.CATALOG_NO) De,
IFSAPP.CUST_ORD_CUSTOMER_API.Get_Name(rm.CUSTOMER_NO) So,
rml.rma_no rma
from
ifsapp.return_material_line rml,
ifsapp.return_material rm,
(select rmh.rma_no,
         substr(rmh.message_text, 6,instr(rmh.message_text,',')-6) rma_line_no,
         rmh.date_entered
  from   ifsapp.return_material_history rmh
  where  rmh.message_text like 'Line%' and
         rmh.message_text like '%received.'
) rmh
where
rml.rma_no=rmh.rma_no and rml.rma_line_no=rmh.rma_line_no
and
rml.rma_no=rm.rma_no
and
rml.contract='OKMMN'
and
rml.inspection_info='PROGRESS'
order by
rmh.date_entered) My initial wish was to go a step further, but I realised I was well out of my league!
There is a quantity per line, so the "real" results would be:
Date_Received Description       Source  Rma     Qty
01/02/2006    WIDGET1           Comp1   100000    1
01/02/2006    WIDGET2           Comp1   100000    2
01/02/2006    WIDGET3           Comp1   100000    1
01/02/2006    WIDGET1           Comp1   100001    3
01/02/2006    WIDGET3           Comp1   100002    1
01/02/2006    WIDGET8           Comp1   100002    1
01/02/2006    WIDGET8           Comp2   100003    2and I managed to get:
Date_Received Description       Source  Rma    
01/02/2006    WIDGET1           Comp1   100000 
01/02/2006    2 x WIDGET2       Comp1   100000 
01/02/2006    WIDGET3           Comp1   100000  
01/02/2006    3 x WIDGET1       Comp1   100001  
01/02/2006    WIDGET3           Comp1   100002 
01/02/2006    WIDGET8           Comp1   100002
01/02/2006    2 x WIDGET8       Comp2   100003by using
decode(rml.qty_received,1,'',to_char(rml.qty_received) || ' x ')
|| IFSAPP.SALES_PART_API.Get_Catalog_Desc(rml.contract,rml.CATALOG_NO) De,So it would show the qty in the description, where it was not 1.
Then I realised there are instances where the same description can appear multiple times, with various quantities, giving this scenario:
Date_Received Description       Source  Rma     Qty
01/02/2006    WIDGET1           Comp1   100000    1
01/02/2006    WIDGET2           Comp1   100000    2
01/02/2006    WIDGET1           Comp1   100000    1
01/02/2006    WIDGET3           Comp1   100002    1
01/02/2006    WIDGET3           Comp1   100002    2which should give:
Date_Received Description                Source  Rma    
01/02/2006    2 x WIDGET1, 2 x WIDGET2   Comp1   100000
01/02/2006    3 x WIDGET3                Comp1   100002 ...but this all has to be possible in a single SQL statement!
I would appreciate, if possible answers to both requirements, if anyone can see a way forward.
Thanks

Answer 1

Many thanks for your suggestion. I managed to apply it, probably not very efficiently, but hey, it works!
SELECT     MAX (da) date_received,
           LTRIM
              (MAX (SYS_CONNECT_BY_PATH (de, ', '))KEEP (DENSE_RANK LAST ORDER BY curr),
              ) AS description,
           so SOURCE, rma
      FROM (SELECT DISTINCT da, de, so, rma,
                            ROW_NUMBER () OVER (PARTITION BY rma, so, da ORDER BY de)
                                                                      AS curr,
                              ROW_NUMBER () OVER (PARTITION BY rma, so, da ORDER BY de)
                            - 1 AS prev
                       FROM (SELECT   TO_CHAR (rmh.date_entered,
                                               'DD/MM/YYYY'
                                              ) da,
                                      ifsapp.sales_part_api.get_catalog_desc
                                                           (rml.contract,
                                                            rml.catalog_no
                                                           ) de,
                                      ifsapp.cust_ord_customer_api.get_name
                                                           (rm.customer_no)
                                                                           so,
                                      rml.rma_no rma
                                 FROM ifsapp.return_material_line rml,
                                      ifsapp.return_material rm,
                                      (SELECT rmh.rma_no,
                                              SUBSTR
                                                 (rmh.MESSAGE_TEXT,
                                                  6,
                                                    INSTR (rmh.MESSAGE_TEXT,
                                                  - 6
                                                 ) rma_line_no,
                                              rmh.date_entered
                                         FROM ifsapp.return_material_history rmh
                                        WHERE rmh.MESSAGE_TEXT LIKE 'Line%'
                                          AND rmh.MESSAGE_TEXT LIKE
                                                                  '%received.') rmh
                                WHERE rml.rma_no = rmh.rma_no
                                  AND rml.rma_line_no = rmh.rma_line_no
                                  AND rml.rma_no = rm.rma_no
                                  AND rml.contract = 'OKMMN'
                                  AND rml.inspection_info = 'PROGRESS'
                             ORDER BY rmh.date_entered))
  GROUP BY rma, so
CONNECT BY prev = PRIOR curr AND rma = PRIOR rma AND so = PRIOR so
           AND da = PRIOR da
START WITH curr = 1