Update Problem - Join With Another Table

Question

I'm trying to convert few MS Access Queries into Oracle. Following is one of the query from MS Access.
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UPDATE [RESULT] INNER JOIN [MASTER]
    ON ([RESULT].[LAST_NAME] = [MASTER].[LAST_NAME])
   AND ([RESULT].[FIRST_NAME] = [MASTER].[FIRST_NAME])
   AND ([RESULT].[DOCUMENT_NUMBER] = [MASTER].[DOCUMENT_NUMBER])
   AND ([RESULT].[BATCH_ID] = [MASTER].[LEAD_ID])
SET [MASTER].[CLOSURE_REASON] = "Closed For Name and Document Number Match",
    [MASTER].[RESULT_ID] = [RESULT].[ID],
    [MASTER].[RESULT_PID] = [RESULT].[PID]
WHERE (([MASTER].[CLOSURE_REASON] Is Null)
   AND ([MASTER].[REC_CODE] = "A1")
   AND ([RESULT].[EVENT_DATE] = [MASTER].[EVENT_DATE])
   AND ([RESULT].[EVENT_TYPE] = "Open")
   AND ([MASTER].[DOCUMENT_NUMBER] Is Not Null)
   AND ([MASTER].[DOCUMENT_NUMBER)] "null"));
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First I received ORA-01779: cannot modify a column which maps to a non key-preserved table Error. I followed different examples (including MERGE) from your
site and modified my original query. Now, I receive ORA-30926: unable to get a stable set of rows in the source tables Error.
Most of the examples showed only one join between the tables but I have to make more joins based on my requirements.
Any help translating this query in to Oracle would be Great. Thanks!

Answer 1

Assuming that the columns you are joining to in the result table are the whole PK or are declared as aunique contraint (i.e. some combination of last_name, first_name, document_number, batch_id, event_date, id, and pid make up the entire PK/unique constraint), then the updateable join view should look something like:
update (select m.last_name, m.first_name, m.document_number, m.lead_id,
               m.closure_reason, m.result_id, r.id, m.result_pid, r.pid
        from master m
           join result r
              on r.last_name = m.last_name and
                 r.first_name = m.first_name and
                 r.document_number = m.document_number and
                 r.batch_id = m.lead_id and
                 r.event_date = m.event_date
        where m.closure_reason is null and
              m.rec_code = 'A1' and
              r.event_type = 'Open' and
              m.document_number is not null and
              m.document_number != 'null')
set closure_reason = 'Closed For Name and Document Number Match',
    result_id = id,
    result_pid = pidThe merge version would look something like:
merge into master
   using (select last_name, first_name, document_number, batch_id,
                 event_date, id, pid
          from result
          where event_type = 'Open') r
   on (r.last_name = m.last_name and
       r.first_name = m.first_name and
       r.document_number = m.document_number and
       r.batch_id = m.lead_id and
       r.event_date = m.event_date)
   when mathed then
      update
      set closure_reason = 'Closed For Name and Document Number Match',
          result_id = id,
          result_pid = pid
      where m.closure_reason is null and
            m.rec_code = 'A1' and
            m.document_number is not null and
            m.document_number != 'null';However, as Hoek pointed out, the combination of last_name, first_name, document_number, batch_id, event_date, id, and pid must point to a unique row in the result table, whether they make up the PK or a unique constraint. If there are, or could be, multiple rows for a particular combination of last_name, first_name, document_number, batch_id, event_date, id, and pid, then you will need to find a way to determine which of those rows should be used to do the update.
John