ORACLE: the date field cannot be stored in hours, minutes, and seconds"

A small test was conducted:

Create Table vipr_airport_rule1
(
Airline varchar2 (2) not null,
Airport varchar2 (3) not null,
Start_time date not null,
End_time date not null,
Num number not null
)

Try to insert data:

Insert into vipr_airport_rule1 values ('CA', 'pek', to_date ('20170101', 'hh24mi '), to_date ('20170101', 'hh24mi'), 0000 );

Successful, but query:

SQL> select * From vipr_airport_rule1;
 
Airline airport start_time end_time num
------------------------------------------------------------------------------
CA pek 2012/9/1 2012/9/1 2: 300

You can only store the data in this format. However, only the time (hours, minutes, And seconds) can be obtained during query ):

SQL> select to_char (end_time, 'hh24mis') from vipr_airport_rule1;
 
To_char (end_time, 'hh24mis ')
----------------------------
020000