HOUR

HOUR(time)

obclient> SELECT HOUR('10:05:03');
+------------------+
| HOUR('10:05:03') |
+------------------+
|               10 |
+------------------+
1 row in set

obclient> SELECT HOUR('272:59:59');
+-------------------+
| HOUR('272:59:59') |
+-------------------+
|               272 |
+-------------------+
1 row in set