combining fields when loading data

[Tom Peters]

Hi,
I'm trying to read a CSV text file into a database. Complication is that none of the fields is a unique key, which I believe my cause problems.
The input data on each row contain a date and an hour, which combination is unique. So I try to combine them into 1 DATETIME field, like this:

mysql> describe Data;
+-------+----------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+----------------------+------+-----+---------+-------+
| STN | smallint(3) unsigned | YES | | NULL | |
| YMDH | datetime | NO | PRI | NULL | |
| HH | smallint(2) unsigned | YES | | NULL | |


mysql> LOAD DATA INFILE '/tmp/some.txt' REPLACE INTO TABLE Data FIELDS TERMINATED BY ',' LINES TERMINATED BY '\r\n' IGNORE 34 LINES (STN, @YMD, @HH) set YMDH = STR_TO_DATE( CONCAT(@YMD, ' ', CAST( (CAST(@HH AS UNSIGNED) - 1 ) AS CHAR(2)) , '%Y%m%d %H:00:00' ) ;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1

The error is not in the separator string ' ': if I replace it by e.g. '-' then I get the same error.

The following more or less works, but gives non-unique rows:
LOAD DATA INFILE '/tmp/some.txt' REPLACE INTO TABLE Data FIELDS TERMINATED BY ',' LINES TERMINATED BY '\r\n' IGNORE 34 LINES (STN, @YMD, HH) SET YMDH = STR_TO_DATE( @YMD, '%Y%m%d' ) ;

How should the top SQL statement look like?
Thanx,
Tom