FND_REQUEST.SUBMIT_REQUEST is an API used to submit a concurrent program in ORACLE Applications.
Parameters:
Application : Short name of the application associated with the concurrent request to be submitted.
Program - Short name of the concurrent program (not the executable) for which the request should be submitted.
Description - Description of the request that is displayed in the Concurrent Requests form (Optional.)
Start_time - Time at which the request should start running, formatted as HH24:MI or HH24:MI:SS (Optional.)
Sub_request - Set to TRUE if the request is submitted from another request and should be treated as a sub-request.
Argument1...100 - Arguments for the concurrent request; up to 100 arguments are permitted. If submitted from Oracle Forms, you must specify all 100 arguments.
Example: Submission of Standard Order Import Program

SET SERVEROUTPUT ON;
DECLARE
     v_request_id                        NUMBER           DEFAULT 0;
    
    --Order Import Parameters
    p_operating_unit                     VARCHAR2(20)    := NULL;
    p_order_source                       VARCHAR2(20)    := 'XYZ';
    p_orig_sys_document_ref              VARCHAR2(20)    := NULL;
    p_operation_code                     VARCHAR2(20)    := NULL;
    p_validate_only                      VARCHAR2(20)    := 'N';
    p_debug_level                        VARCHAR2(20)    := '1';
    p_num_instances                      VARCHAR2(20)    := '4';
    p_sold_to_org_id                     VARCHAR2(20)    := NULL;
    p_sold_to_org                        VARCHAR2(20)    := NULL;
    p_change_sequence                    VARCHAR2(20)    := NULL;
    p_perf_param                         VARCHAR2(20)    := 'Y';
    p_rtrim_data                         VARCHAR2(20)    := 'N';
    p_pro_ord_with_null_flag             VARCHAR2(20)    := 'Y';
    p_default_org_id                     VARCHAR2(20)    := '83';
    p_validate_desc_flex                 VARCHAR2(20)    := 'N';
    -- End of Parameters -----
    v_context varchar2(100);
/* When ever we use APPS API’s its always better to APPS initialize context.*/
    FUNCTION set_context( i_user_name    IN  VARCHAR2
                     ,i_resp_name    IN  VARCHAR2
                     ,i_org_id       IN  NUMBER)
RETURN VARCHAR2
IS
v_user_id             NUMBER;
v_resp_id             NUMBER;
v_resp_appl_id NUMBER;
v_lang                   VARCHAR2(100);
v_session_lang VARCHAR2(100):=fnd_global.current_language;
v_return              VARCHAR2(10):='T';
v_nls_lang          VARCHAR2(100);
v_org_id              NUMBER:=i_org_id;
/* Cursor to get the user id information based on the input user name */
CURSOR cur_user
IS
    SELECT     user_id
    FROM       fnd_user
    WHERE      user_name  =  i_user_name;
/* Cursor to get the responsibility information */
CURSOR cur_resp
IS
    SELECT     responsibility_id
                     ,application_id
                    ,language
    FROM       fnd_responsibility_tl
    WHERE      responsibility_name  =  i_resp_name;
/* Cursor to get the nls language information for setting the language context */
CURSOR cur_lang(p_lang_code VARCHAR2)
IS
    SELECT    nls_language
    FROM      fnd_languages
    WHERE     language_code  = p_lang_code;
BEGIN
    /* To get the user id details */
    OPEN cur_user;
    FETCH cur_user INTO v_user_id;
    IF cur_user%NOTFOUND
    THEN
        v_return:='F';
       
    END IF; --IF cur_user%NOTFOUND
    CLOSE cur_user;
    /* To get the responsibility and responsibility application id */
    OPEN cur_resp;
    FETCH cur_resp INTO v_resp_id, v_resp_appl_id,v_lang;
    IF cur_resp%NOTFOUND
    THEN
        v_return:='F';
       
    END IF; --IF cur_resp%NOTFOUND
    CLOSE cur_resp;
    /* Setting the oracle applications context for the particular session */
    fnd_global.apps_initialize ( user_id      => v_user_id
                                ,resp_id      => v_resp_id
                                ,resp_appl_id => v_resp_appl_id);
    /* Setting the org context for the particular session */
    mo_global.set_policy_context('S',v_org_id);
    /* setting the nls context for the particular session */
    IF v_session_lang != v_lang
    THEN
        OPEN cur_lang(v_lang);
        FETCH cur_lang INTO v_nls_lang;
        CLOSE cur_lang;
        fnd_global.set_nls_context(v_nls_lang);
    END IF; --IF v_session_lang != v_lang
    RETURN v_return;
EXCEPTION
WHEN OTHERS THEN
    RETURN 'F';
END set_context;

BEGIN
      -- Setting the context ----
      v_context := set_context('&V_USER_NAME','&V_RESPONSIBILITY',82);
      IF v_context = 'F'
      THEN
        DBMS_OUTPUT.PUT_LINE('Error while setting the context');       
      END IF;
      DBMS_OUTPUT.PUT_LINE('Submit Order Import Concurrent Program');
      v_request_id:=  FND_REQUEST.SUBMIT_REQUEST (
               application  =>  'ONT'
              ,program      =>  'OEOIMP'
              ,description  =>  'Order Import'
              ,start_time   =>  SYSDATE
              ,sub_request  =>  NULL
              ,argument1    =>  p_operating_unit
              ,argument2    =>  p_order_source
              ,argument3    =>  p_orig_sys_document_ref
              ,argument4    =>  p_operation_code
              ,argument5    =>  p_validate_only
              ,argument6    =>  p_debug_level
              ,argument7    =>  p_num_instances
              ,argument8    =>  p_sold_to_org_id
              ,argument9    =>  p_sold_to_org
              ,argument10   =>  p_change_sequence
              ,argument11   =>  p_perf_param
              ,argument12   =>  p_rtrim_data
              ,argument13   =>  p_pro_ord_with_null_flag
              ,argument14   =>  p_default_org_id
              ,argument15   =>  p_validate_desc_flex
             );
/* we have submitted the request and we need to check the status of the request and do any action based on that.so we need to wait for the request
Wait request is provided below.*/



IF request_id = 0 THEN
    fnd_file.put_line(fnd_file.log, 'Request Not Submitted.');
ELSE

Arguments (input)


   request_id
        The request ID of the program to wait on.

   interval
        Time to wait between checks.  This is the number of seconds to sleep.  
 The default is 60 seconds.

   max_wait
        The maximum time in seconds to wait for the requests completion.


Arguments (output)


   phase
        The user friendly request phase from FND_LOOKUPS lookup_type ='CP_PHASE_CODE'.

   status
        The user friendly request status from FND_LOOKUPS lookup_type ='CP_STATUS_CODE'.

   dev_phase
        The request phase as a constant string that can be used for program 
  logic comparisons.

   dev_status
        The request status as a constant string that can be used for program 
 logic comparisons.

   message
        The completion message supplied if the request has completed.
v_interval := 20;--20 sec wait

lc_call_status := fnd_concurrent.wait_for_request(v_request_id, v_interval, v_max_wait, request_phase, request_status, dev_request_phase, dev_request_status, request_status_mesg);
END IF;
IF lc_call_status = TRUE THEN
IF dev_request_phase!= 'Completed' OR
dev_request_status IN ('Cancelled','Error','Terminated') THEN
DBMS_OUTPUT.PUT_LINE('STATUS=JOB FAILED');
END IF;
ELSE
DBMS_OUTPUT.PUT_LINE('WAIT FOR REQUEST FAILED - STATUS UNKNOWN');
DBMS_OUTPUT.PUT_LINE('STATUS=JOB FAILED');
END IF;

       COMMIT;
       DBMS_OUTPUT.PUT_LINE('Request_id: '||v_request_id);
EXCEPTION WHEN OTHERS THEN        
       DBMS_OUTPUT.PUT_LINE(SQLCODE||' Error :'||SQLERRM);
END;