Oracle logoff trigger to get sql's executed by session - oracle

Question

I have created a table which contains the host names of all the trusted sources. I have written a oracle log off trigger to fetch details of all the sql executed by that session if the connection's host is not amongst the snif_session table. I am taking the output to a utl_file output which contains the sid, hostname, time connected.
SQL> select * from snif_Session;
ALLOWED_HOST
--------------------------------------------------
RND1
WORKGROUP\RND1
The place where i am getting stuck is what query to use to get all the sql's executed by that particular session ( i can get the sid from v$mystat).
does this work best :
select a.sql_id
,b.sql_text
from dba_hist_active_sess_history a
,dba_hist_sqltext b
where a.sql_id=b.sql_id
or
select s.sid
, s.serial#
, a.sql_text
from v$session s
join v$sqlarea a
on a.hash_value = s.sql_hash_value ;
This is the code i have written (block) which i will be placing inside a trigger.
declare
machine_id varchar2(50);
val int;
auth_terminal varchar2(50);
check_machine varchar2(1000);
mydate char(50);
osuser_1 varchar2(50);
sid_1 int;
sql_query_1 varchar2(5000);
machine_1 varchar2(50);
trace_info UTL_FILE.FILE_TYPE;
begin
select machine into check_machine
from v$session
where sid in (select distinct(sid) from v$mystat) ;
select count(*) into val
from snif_session
where allowed_host=check_machine;
if ( 1=val) then
dbms_output.put_line(check_machine|| ' dont check host' );
else
dbms_output.put_line(check_machine || ' check host' );
end if;
select osuser,sid,machine
into osuser_1,sid_1,machine_1
from v$session
where sid in (select distinct(sid) from v$mystat);
SELECT TO_char(systimestamp,'mm/dd/yyyy HH24:MI:SS') into mydate
FROM DUAL;
dbms_output.put_line(mydate || sid_1 || ' ' || osuser_1 || ' '|| machine_1);
trace_info := UTL_FILE.FOPEN('UTL_DIR', 'trace_info_file.txt', 'W');
UTL_FILE.PUTF(trace_info,mydate||' '||sid_1||' '||osuser_1||' '|| machine_1);
UTL_FILE.FCLOSE(trace_info);
EXCEPTION
WHEN utl_file.invalid_path THEN
raise_application_error(-20000, 'ERROR: Invalid PATH FOR file.');
end;
I need to include the 'sql queries' also executed by session in the utl_file output.

Answer 1

"I need to include the 'sql queries' also executed by session"
Neither of your suggested queries will give you all the SQL executed by a session.
V$SESSION is a dynamic view, so it just shows what is happening in a session right now.
DBA_HIST_ACTIVE_SESS_HISTORY is a series of snapshots of running SQL. It is intended for performance profiling, and as such it is basically a random sub-set of active statements. Also, it is part of the Diagnostics and Tuning Pack: you will be in breach of your license if you use it without paying the additional charge.
It appears that what you really need is an audit trail. Instead of rolling your own, why not investigate the functionality Oracle already has? There's AUDIT to track DDL activity. There's Fine-grained Auditing to monitor lower-level DML. Find out more.