function testDateToId()
 {
     $dateStr = "2006-04-02 10:20:08.123456";
     $id = ScheduleGroup::dateToId($dateStr);
     $expected = "20060402102008123";
     if ($id != $expected) {
         $this->fail("Did not convert date to ID correctly #1: {$id} != {$expected}");
     }
     $dateStr = "2006-04-02 10:20:08";
     $id = ScheduleGroup::dateToId($dateStr);
     $expected = "20060402102008000";
     if ($id != $expected) {
         $this->fail("Did not convert date to ID correctly #2: {$id} != {$expected}");
     }
 }