How to see today compiled object in Oracle? Is there a way to find objects that were compiled today?
I think the timestamp column of dba_objects is what you are after:

create table t(id integer);
create function f return integer as
  n integer;
begin
  select count(*) into n from t;
  return n;
end;
/

select status, timestamp from user_objects where object_name='F';
STATUS  TIMESTAMP           
------- ------------------- 
VALID   2011-09-05:11:01:52 

insert into t(id) values (1);
select f() from dual;             -- ***no recompile needed***

select status, timestamp from user_objects where object_name='F';
STATUS  TIMESTAMP           
------- ------------------- 
VALID   2011-09-05:11:01:52 

alter table t add dummy integer;  -- ***invalidates f()***

select status, timestamp from user_objects where object_name='F';
STATUS  TIMESTAMP           
------- ------------------- 
INVALID 2011-09-05:11:01:52 

select f() from dual;             -- ***forces recompile***
select status, timestamp from user_objects where object_name='F';
STATUS  TIMESTAMP           
------- ------------------- 
VALID   2011-09-05:11:01:53       -- ***note the different timestamp*** 


so to get all functions compiled today for example:

select * 
from dba_objects
where to_date(substr(timestamp,1,10), 'yyyy-mm-dd')&gt;=trunc(sysdate)
      and object_type='FUNCTION';


--edit

it may be safer to use last_ddl_time instead (see @Alex's comment below), but the caveat is that last_ddl_time is also changed on grants and revokes.