chess program in plsql

DECLARE

  n number:=8;

v_wh varchar2(3):=' # ';

v_bl varchar(3):=' * ';

v_str varchar2(100);

Begin

   For i in 1..n loop     

    -- dbms_output.put(v_wh);

     For j in 1..n Loop          

        If mod(j,2)=0 Then 

          dbms_output.put(v_bl);

         ELSE

         dbms_output.put(v_wh);

        End If;      

     End Loop;

     v_str := v_wh;

     v_wh :=v_bl;

     v_bl :=v_str;

     dbms_output.new_line;     

End Loop;   

End

locked_objects_info_vu

select   owner,
   object_name,
   object_type,
   sid_serial#,
   status,
   osuser,
   CLIENT_Info,
   client_identifier,
  PROCESS,BLOCKING_SESSION,BLOCKING_SESSION_STATUS,SECONDS_IN_WAIT,
   EVENT,WAIT_CLASS,STATE,SQL_ID,PREV_SQL_ID, machine
from
(
select
   c.owner,
   c.object_name,
   c.object_type,
   b.sid||','||b.serial# sid_serial#,
   b.status,
   b.osuser,
  (select client_info from v$session where PROCESS=b.PROCESS and rownum=1) user_function,
  client_info,CLIENT_IDENTIFIER,
  B.PROCESS,B.BLOCKING_SESSION,B.BLOCKING_SESSION_STATUS,B.SECONDS_IN_WAIT,
   B.EVENT,B.WAIT_CLASS,B.STATE,B.SQL_ID,B.PREV_SQL_ID, b.machine
from v$locked_object a , v$session b,dba_objects c
where b.sid = a.session_id
and   a.object_id = c.object_id
)