update temp_table t set
  t.creation_date = (select h.update_date
                     from header_table h
                     where h.id_column = t.id_column
                    )
where exists (select null 
              from header_table h1
              where h1.id_column = t.id_column
             )

UPDATE regal.regal_om_edi850_worktab_temp a
SET a.creation_date = (SELECT b.creation_date 
FROM regal.regal_om_edi850_header_tab b
WHERE a.original_system_reference = b.original_system_reference)
WHERE EXISTS (SELECT b.creation_date 
FROM regal.regal_om_edi850_header_tab b
WHERE a.original_system_reference = b.original_system_reference)	

SELECT a.creation_date             hdr_c_date, 
       b.creation_date             worktab_c_date, 
       a.original_system_reference hdr_ori_sys_ref, 
       --    b.original_system_reference worktab_ori_sys_ref, 
       a.tprt_number               hdr_tpt_num, 
       b.tprt_number               worktab_tpt_num 
FROM   regal.regal_om_edi850_header_tab a, 
       regal.regal_om_edi850_worktab_temp b 
WHERE  a.original_system_reference = b.original_system_reference 
AND a.tprt_number = b.tprt_number

DECLARE 
    CURSOR c1 IS 
      SELECT a.creation_date             hdr_c_date, 
             b.creation_date             worktab_c_date, 
             a.original_system_reference hdr_ori_sys_ref, 
             --    b.original_system_reference worktab_ori_sys_ref, 
             a.tprt_number               hdr_tpt_num, 
             b.tprt_number               worktab_tpt_num 
      FROM   regal.regal_om_edi850_header_tab a, 
             regal.regal_om_edi850_worktab_temp b 
      WHERE  a.original_system_reference = b.original_system_reference 
             AND a.tprt_number = b.tprt_number; 
--AND a.original_system_reference LIKE 'JCP01-100009670-03440269-94656' 
BEGIN 
    FOR crec IN c1 LOOP 
        dbms_output.Put_line('TPRT Number: '                ||crec.hdr_tpt_num     ||' ' ||
                              'original system reference : '  ||crec.hdr_ori_sys_ref  ||' ' ||
                              'Header Creation date : '       ||crec.hdr_c_date ||' ' ||'  '||
                              'Worktab creation date : '      ||crec.worktab_c_date); 
    /*UPDATE regal.regal_om_edi850_worktab_temp 
    SET creation_date=CREC.hdr_c_date 
    WHERE original_system_reference = CREC.original_system_reference 
    and a.tprt_number = b.tprt_number; 
    */ 
    END LOOP; 
END; 

SELECT a.creation_date             header_c_date, 
       b.creation_date             lines_c_date
FROM   oe_order_headers_all_bkp a, 
       oe_order_lines_all_bkp b
where  a.header_id = b.header_id
and a.creation_date is not null
       
       
update oe_order_lines_all_bkp
set creation_date=sysdate
       
update oe_order_lines_all_bkp a
set a.creation_date=(select creation_date from oe_order_headers_all_bkp b where a.header_id = b.header_id)

declare
CURSOR C1 
IS
SELECT a.creation_date             header_c_date, 
       b.creation_date             lines_c_date
FROM   oe_order_headers_all_bkp a, 
       oe_order_lines_all_bkp b
       where  a.header_id = b.header_id ;
BEGIN
FOR CREC IN C1 LOOP
dbms_output.put_line('Headers Creation Date: '||crec.header_c_date||' '||'Lines C Data  : '||crec.lines_c_date);
update oe_order_lines_all_bkp a
set a.creation_date=(select creation_date from oe_order_headers_all_bkp b where a.header_id = b.header_id);
END LOOP;
end;