How to find how many users are connected to Oracle Applications :

 How do we know how many users are connected to Oracle Applications.

1. Enable Profile Option "Sign-On Audit" at "Form" level.
2. Run "Purge Signon Audit" request.
3. Security:Users -> Monitor" option
4  or with the below sql query  mentioned below.

SQL> select distinct fu.user_name User_Name,fr.RESPONSIBILITY_KEY Responsibility 
from fnd_user fu, fnd_responsibility fr, icx_sessions ic
where fu.user_id = ic.user_id AND
fr.responsibility_id = ic.responsibility_id AND
ic.disabled_flag='N' AND
ic.responsibility_id is not null AND
ic.last_connect like sysdate;

5. Can use this SQL statement to count concurrent_users in Oracle apps:

SQL> select count(distinct d.user_name) from apps.fnd_logins a,
v$session b, v$process c, apps.fnd_user d
where b.paddr = c.addr
and a.pid=c.pid
and a.spid = b.process
and d.user_id = a.user_id
and (d.user_name = 'USER_NAME' OR 1=1);

++++++To Know the GSS++++++
Gathering Statistics is a REQUIRED  task . . .  unless your Statistics are CURRENT and upto date.
However, your Client  Data is probably changing that quickly you can merely Gather Schema Statistics (ALL) twice a Week.
Please execute the SQL-Script below to report the FND_STATS_HISTORY (Gather Schema Stats).

sqlplus APPS/appspwd

     SQL> SET PAGESIZE 200
        COLUMN  sowner  format A15     HEADING 'Scheam Name'
        COLUMN  strtim  format A18     HEADING 'Schema|Start Time'
        COLUMN  endtim  format A18     HEADING 'Schema|End-Time'
        COLUMN  stimes  format A18     HEADING 'Elapsed Time|Duration'

        TTITLE  CENTER  'Apps Gather Schema Statistics '             skip 1 -
                CENTER  'eBusiness Gather Schema Statistics History' skip 2
                
        alter session set NLS_DATE_FORMAT = 'DD-MON-YYYY HH24:MI:SS';

        SELECT SCHEMA_NAME sowner, 
TO_CHAR(LAST_GATHER_START_TIME,'DD-MON-YY HH24:MI:SS') strtim,
to_char(LAST_GATHER_END_TIME,'DD-MON-YY HH24:MI:SS') endtim,
to_char(trunc(sysdate) + (nvl(LAST_GATHER_END_TIME,sysdate)
- LAST_GATHER_START_TIME),'hh24:mi:ss') stimes
FROM applsys.FND_STATS_HIST 
WHERE LAST_GATHER_DATE >= '09-MAY-13'
 AND upper(SCHEMA_NAME) like '%'
 AND object_type = 'SCHEMA'
ORDER BY sowner, strtim; 

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