short way truncate table sys.aud$ =)))

BEGIN
  DBMS_AUDIT_MGMT.init_cleanup(
    audit_trail_type         => DBMS_AUDIT_MGMT.AUDIT_TRAIL_ALL,
    default_cleanup_interval => 24 /* hours */);
END;
/

SET SERVEROUTPUT ON
BEGIN
  IF DBMS_AUDIT_MGMT.is_cleanup_initialized(DBMS_AUDIT_MGMT.AUDIT_TRAIL_AUD_STD) THEN
    DBMS_OUTPUT.put_line('YES');
  ELSE
    DBMS_OUTPUT.put_line('NO');
  END IF;
END;
/

BEGIN
  DBMS_AUDIT_MGMT.set_last_archive_timestamp(
    audit_trail_type  => DBMS_AUDIT_MGMT.AUDIT_TRAIL_AUD_STD,
    last_archive_time => SYSTIMESTAMP-31);
END;
/

create purge audit job

--create STANDARD_AUDIT_TRAIL_PURGE_JOB
BEGIN
DBMS_AUDIT_MGMT.CREATE_PURGE_JOB (
AUDIT_TRAIL_TYPE => DBMS_AUDIT_MGMT.AUDIT_TRAIL_AUD_STD,
AUDIT_TRAIL_PURGE_INTERVAL => 24,
AUDIT_TRAIL_PURGE_NAME => 'Standard_Audit_Trail_Purge_Job',
USE_LAST_ARCH_TIMESTAMP => TRUE );
END;
/

Or audit all purge job:

BEGIN
DBMS_AUDIT_MGMT.CREATE_PURGE_JOB (
AUDIT_TRAIL_TYPE => DBMS_AUDIT_MGMT.AUDIT_TRAIL_ALL,
AUDIT_TRAIL_PURGE_INTERVAL => 24,
AUDIT_TRAIL_PURGE_NAME => 'ALL_Audit_Trail_Purge_Job',
USE_LAST_ARCH_TIMESTAMP => TRUE );
END;
/

create job to update what can job delete from audit

BEGIN
  SYS.DBMS_SCHEDULER.CREATE_JOB
    (
       job_name        => 'SYS.MOVE_LAST_TIMESTAMP_FORWARD'
      ,start_date      => trunc (SYSTIMESTAMP) 
      ,repeat_interval => 'FREQ=DAILY;INTERVAL=1'
      ,end_date        => NULL
      ,job_class       => 'DEFAULT_JOB_CLASS'
      ,job_type        => 'PLSQL_BLOCK'
      ,job_action      => '
BEGIN
  DBMS_AUDIT_MGMT.set_last_archive_timestamp(
   audit_trail_type  => DBMS_AUDIT_MGMT.AUDIT_TRAIL_AUD_STD,
   last_archive_time => SYSTIMESTAMP-31);
'
      ,comments        => NULL
    );
end;
/

BEGIN
DBMS_SCHEDULER.set_attribute( name => '"SYS"."MOVE_LAST_TIMESTAMP_FORWARD"', attribute => 'auto_drop', value => FALSE);
DBMS_SCHEDULER.enable(name=>'"SYS"."MOVE_LAST_TIMESTAMP_FORWARD"');
END; 
/

SELECT * FROM dba_audit_mgmt_config_params;
SELECT * FROM dba_audit_mgmt_last_arch_ts;
select * from DBA_AUDIT_MGMT_CLEAN_EVENTS;

Standard_Audit_Trail_Purge_Job

STOP:

BEGIN
  DBMS_AUDIT_MGMT.set_purge_job_status(
    audit_trail_purge_name   => 'STANDARD_AUDIT_TRAIL_PURGE_JOB',
    audit_trail_status_value => DBMS_AUDIT_MGMT.PURGE_JOB_DISABLE);
end;
/

Drop:

BEGIN
DBMS_AUDIT_MGMT.DROP_PURGE_JOB(
  AUDIT_TRAIL_PURGE_NAME  => 'STANDARD_AUDIT_TRAIL_PURGE_JOB');
END;

Manual run:

BEGIN
  DBMS_AUDIT_MGMT.clear_last_archive_timestamp(
    audit_trail_type     =>  DBMS_AUDIT_MGMT.AUDIT_TRAIL_ALL);
END;
/

list of DBMS_AUDIT_MGMT. –>AUDIT_TRAIL_ALL<-- can be found here
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