How to create unique index on a View

Question

Hi All,
11.2.0.1
How do I create an index on a view or any workaround that my view wont get duplicates?
SQL> create unique index indx01 on db_backup_details_vw(id);
create unique index indx01 on db_backup_details_vw(id)
ERROR at line 1:
ORA-01702: a view is not appropriate here
Thanks a lot,
Kinz

Answer 1

I'm thinking of using a distinct clause here.
if i get 5 duplicate rows in my selection set because of the join condition, can't i discard the remaining 4 using a distinct clause.
Observe this
SQL> select * from a;
T1 T2
1 4
2 4
3 4
SQL> select * from b;
T1 T2
1 4
2 5
in both a,b t1 is the primary key. so we'll write a join on t2 (non PK).
SQL> select b.t1,b.t2 from a,b where a.t2=b.t2;
T1 T2
1 4
1 4 -- duplicates
1 4
Now create view with distinct clause
create view ab as select distinct b.t1,b.t2 from a,b where a.t2=b.t2;
SQL> select * from ab;
T1 T2
---------- ---------- -- no duplicates
1 4
CSM