Query on Data Block based on View

Question

Hi,
I am new to forms and am trying to modify an existing form which currently works in the following way :
The same form is used for insert/updates/queries.
The data block is based on a table and a post query trigger is written which updates the other text items on the canvas(which come from different tables) based on the values returned by the data block. Since the query functionality is based only on the table, you cannot query on the other items that are on the canvas. I need to make the query work on the other items that come from different tables.
I created a view which joins all the tables but when I query although it returns the right record I get an error message " Cannot insert into or update view"
I'm not sure what the best way to resolve this is ?
Any suggestions ?
Thanks
Preeti

Answer 1

Thanks for the replies.
I created an updateable view and an instead of trigger. The Form is now queryable on all fields and the insert to the table works beautifully.
However, now I'm getting an error on Update. Updating any column on the form results in a
ORA-01733: virtual column not allowed here
FRM-40501: ORACLE error: unable to reserve record for update or delete.
The code for the view is :
select a.*,
B.vendor_name as Supplier_name,
     'PRE' AS TO_OWNER,
     C.vendor_site_code as supplier_site,
     ARCH.vendor_name AS Architect,
     p.segment1 as Project,
     ph.segment1 as PO_number,
     decode(a.interface_status,'I','Interfaced', 'U', 'UnInterfaced',
     'P', 'Partial',null) Interface_display_status,
     decode(a.approval_status,'A','Approved', 'P', 'Partial',
     'R', 'Rejected', 'U','Unapproved',null) Approval_display_status
from idc_aia_g702 a, po_vendors b,
po_vendor_sites_all C,
PO_VENDORS ARCH,
pa_projects_all p,
po_headers_all ph
where b.vendor_id = a.vendor_id
AND A.vendor_site_Id (+) = C.vendor_site_id
AND A.VIA_ARCHITECT_VENDOR_ID = ARCH.VENDOR_ID (+)
and a.project_id = p.project_id
and a.po_header_id = ph.po_header_id;
I know I have to do something on either the data block property palette or the individual item property palette and clicking on any field within the form in order to update it results in the error mentioned above.
Shd I have all the item props as Query Only set to Yes ? or the ones for Table A as Query Only set to N and the other table columns as Y ?
Thanks
Preeti