Tabular forms based on pipelined functions - can it be done?

Question

Hi there,
Pipelined functions are great, specially when you want to encapsulate the access to tables instead of just SELECTing from them (what I am doing a lot in my current project.)
However Apex 4 does not like them, at least not for tabular forms...
I want to handle myself the update/insert/delete process, so I don't need the MRU default functionality (all the access to the data is via APIs). But at the same time I want to just SELECT from my pipelined function and set the item types using the builder interface as with any tabular form (without having to use the apex_item API). Also I want to be able to use tabular form validation.
To start with, you can only create a tabular form based on a table or view. To overcome this issue, I created a dummy view with the fields I wanted and created my tabular form on it. Then I changed the FROM clause to FROM TABLE(myfunction). It didn't work as it seems it tries to select the ROWID for each row... Of course my pipelined function doesn't return one but I don't need one anyway as I will be doing the data manipulation myself based on the PK.
For this to work, I had to create a collection, populate it with the result of the pipelined function in a page process every time the page is loaded, create a view on that collection and base the tabular form on the view... A lot of work and overhead for something that should be very simple in principle.
Then, I found out that if I remove the default MRU process that is automatically created, the tabular form validations stop working (as I posted in another thread). So I have to leave a "dummy" MRU process there with condition = never for it to work.
The application I am working on is all based on API calls and pipelined functions so all this work has to be repeated for each tabular form that is needed.
If it was possible to base a tabular form directly on a pipelined function it would be such an elegant solution.
Is there a better way to implement this? Shouldn't Apex be more compatible with pipelined functions? (at least in regards to tabular forms, they work well with normal forms, reports, LOVs etc)
Thanks
Luis

Answer 1

As I mentioned before, I don't handle inserts (well, I cheat).... On my page, there is a form to set up a request - prompts for a few things, and when submitted, calls a stored procedure:
:P2_REQUEST_RESULT := Simon.Apex_Campus_Guest.Setup_Request(:P2_GROUP_NAME,
       :P2_COAS_ORGN, :P2_START_DATE, :P2_END_DATE, :P2_Quantity, :P2_Generic_Names);
Which creates an APEX collection, which in turn is made visible via a pipelined function turned into a view:
create or replace view Apex_Campus_Guest_Request_va as
select seq_no,
        user_name,
       group_name,
        comments
  from table ( Apex_Campus_Guest.Request_Result )
I have a second region which is tabular form on a query - conditional on select 1 from Simon.apex_campus_guest_request_va (the view defined above).
When this submitted, I have standard MRU and MRD processes (Seq_No is the primary key). This then runs into the appropriate trigger - the update trigger is as follows:
trigger Apex_Campus_Guest_Req_Upd
instead of update on Apex_Campus_Guest_Request_va
for each row
declare
        cg_rec  campus_guest_maint.rec;
begin
        cg_rec := Campus_Guest_Maint.Request(
                        name => :new.user_name,
                        group_name => :new.group_name,
                        comments => :new.comments);
end;I don't know off hand why it isn't asking for a rowid - but may be that I specified a PKEY column. The insert case fails, as it tries to add a "Returning" statement in the original select. I actually find that annoying as a function is defined to allocate the PKEY from a sequence, so it doesn't need to ask for it that way.