how I can get log from database in oracle?

Question

Hi
Last day my head judge me because he face with some problem that he didnot has it before!
but I didnt do any thing with database and also our company CM database is so critical !
In this case can he proof what I do with database???
Oracle have any log!
some functaion updating in last 2days that I didnt update it and he also...
please help me,how I can proof who do the mistake.
how I can find who with which user connect to database and update or change some thing...

Answer 1

You can see when database objects were last modified (recompiled/altered/created) this way:

SELECT object_name, last_ddl_time
FROM dba_objects
ORDER BY last_ddl_time DESC;

Answer 2

There are redo logs (which are used to recover from a backup), but they don't record the username, workstation or anything else that identifies who made a data change.