Instead of trigger and merge

Question

Hi,
I have created view and instead of insert, delete, update triggers on it. It is working fine for insert, delete, update. However, the application uses lots of merge command. For merge command on the view, I get following error
ORA-01446: cannot select ROWID from, or sample, a view with DISTINCT, GROUP BY, etc.
I dont have any rowid mentioned in merge command. Is there way how to make MERGE working over view with instead of triggers ?
Thanks for advices.

Answer 1

my view is simple, it is "union all" operation over several tables without any other conditions, original tables are index organized with PK consisting of 4 columns
EDIT:
here is simplified example of the problem
create table val_00 (
id number(10),
data varchar2(100),
constraint pk_val_00 primary key (id) validate
) organization index;
create table val_01 (
id number(10),
data varchar2(100),
constraint pk_val_01 primary key (id) validate
) organization index;
create or replace view val as
select id, data from (
select id, data from val_00
union all
select id, data from val_01
create or replace trigger trg_val_ins
instead of insert on val
referencing new as new
for each row
begin
case mod(:new.id, 2)
when 0 then insert into val_00 (id, data) values (:new.id, :new.data);
when 1 then insert into val_01 (id, data) values (:new.id, :new.data);
end case;
end;
create or replace trigger trg_val_upd
instead of update on val
referencing old as old new as new
for each row
begin
if updating('id') then
raise_application_error(-20999, 'you can not update primary key in val');
end if;
case mod(:new.id, 2)
when 0 then update val_00 set data = :new.data where id = :old.id;
when 1 then update val_01 set data = :new.data where id = :old.id;
end case;
end;
create or replace trigger trg_val_del
instead of delete on val
referencing old as old
for each row
begin
case mod(:old.id, 2)
when 0 then delete from val_00 where id = :old.id;
when 1 then delete from val_01 where id = :old.id;
end case;
end;
insert into val values (1, 'one');
insert into val values (2, 'two');
insert into val values (3, 'three');
insert into val values (4, 'four');
insert into val values (5, 'five');
delete from val where id = 2;
insert into val values (2, 'twooo');
update val set data = 'two' where id = 2;
commit;
merge into val using
( select 10 as id, 'ten' as data from dual ) newdata
on (val.id = newdata.id)
when matched then
update set val.data = newdata.data
when not matched then
insert (id, data) values (newdata.id, newdata.data);
ERROR at line 1:
ORA-01446: cannot select ROWID from, or sample, a view with DISTINCT, GROUP BY, etc.
Edited by: kamilp on Aug 18, 2012 8:17 AM