Need to know base table and base column name for Oracle view columns

Question

I am trying to load metadata for some views and that requires me to know what the final table and column name would be corresponding to the view column.
For example, if I have a view x_v that is select a,b from x_v2; and x_v2 is a view that is select a,b,c from x;
I need to get the following information.
View View Col Base Table Base Col
X_V A X A
X_V B X B
and so on.
Is it possible to get this programmatically using any SYS schema tables or Dependency tables?
I tried an indirect approach wherein I lock tables using LOCK TABLE or FOR UPDATE OF. But I'm not too sure if I can go down to the level of individual view columns.
Can you help me with this?

Answer 1

Thanks. I was looking at some indirect approaches.
I came up with this script that does it faster than dependencies but thats just for tables and not column mapping.
declare
cursor bt(cp_sid number) is
select u.name uname, o.name oname
from sys.obj$ o, sys.user$ u
where o.obj# in (select id1
from v$lock
where sid=cp_sid)
and u.user# =o.owner#;
cursor c_sid is
select sid
from v$session
where audsid =userenv('sessionid');
l_sid number;
l_view varchar2(100):= 'PER_PEOPLE_V';
l_schema varchar2(10):= 'APPS';
begin
open c_sid;
fetch c_sid into l_sid;
close c_sid;
dbms_output.put_line('SID: '||l_sid);
execute immediate 'lock table '||l_schema||'.'||l_view||' in row share mode nowait';
for i in bt(l_sid) loop
dbms_output.put_line(i.uname||'.'||i.oname);
execute immediate 'alter table '||i.uname||'.'||i.oname||' disable table lock';
execute immediate 'alter table '||i.uname||'.'||i.oname||' enable table lock';
end loop;
end;
It basically uses locks on views to verify locks on the base tables.
Just wondering, can we use FOR UPDATE OF statements to get to the columns?