datetime 2013-11-12 10:34:33.000 value

[jongse park]

How to prevent to inserting invalid values for datetime datatype?

I created a table like this;
------
create table t1 (a datetime);
and then insert values;

insert into t1 values ('2013-11-11 09:22:32');
Qeury OK, 1 row affected (0.00 sec)

But,
insert into t1 values (''2013-11-11 09:22:32.000');
Qeury OK, 1 row affected (0.06 sec)
insert into t1 values (''2013-11-11 09:22:32.012200');
Qeury OK, 1 row affected (0.07 sec)
insert into t1 values (''2013-11-11 09:22:32.01220011232132');
Qeury OK, 1 row affected (0.07 sec)

there is no error for inserting invalid datetime.
is this bug?

Please tell me. how can I prevent from inserting it?

Thanks