CREATE TABLE `cur_work_plan` (
  `PERSON_ID` int( 11 ) NOT NULL default '0',
  `DATE_VAL` date NOT NULL default '0000-00-00',
  `BEGIN_TIME` time NOT NULL default '00:00:00',
  `END_TIME` time NOT NULL default '00:00:00'
) TYPE=InnoDB;

mysql> select * from cur_work_plan where (date_val + begin_time) > now();
Empty set ( 0 . 00  sec)

mysql> select PERSON_ID, DATE_VAL, BEGIN_TIME, END_TIME from cur_work_plan;
+ -----------+------------+------------+----------+
 
| PERSON_ID | DATE_VAL   | BEGIN_TIME | END_TIME |
+ -----------+------------+------------+----------+
 
|        101  |  2003 - 12 - 01  |  08 : 00 : 00    |  16 : 00 : 00  |
|        101  |  2003 - 12 - 03  |  10 : 00 : 00    |  11 : 00 : 00  |
|        101  |  2003 - 12 - 06  |  06 : 00 : 00    |  07 : 00 : 00  |
|        102  |  2003 - 12 - 01  |  17 : 00 : 00    |  19 : 00 : 00  |
+ -----------+------------+------------+----------+
 
 4  rows in set ( 0 . 00  sec)

select * from cur_work_plan where
date_val > CURDATE() or (date_val = CURDATE() and begin_time > curtime());