ORA-14400: inserted partition key does not map to any partition

You can split the partition if you have defined the max value or default partition if not you can either add a new partition


SQL> alter table part_test add partition part_oct values less than (to_date('2012-10-30','yyyy-mm-dd'));

Table altered.

or
 use interval partitioning ...

SQL> insert into part_test values (to_date('2012-10-02','yyyy-mm-dd'),'inserting for aug');
insert into part_test values (to_date('2012-10-02','yyyy-mm-dd'),'inserting for aug')
            *
ERROR at line 1:
ORA-14400: inserted partition key does not map to any partition


SQL> alter table part_test set interval(numtodsinterval(1,'day'));

Table altered.

SQL> insert into part_test values (to_date('2012-10-02','yyyy-mm-dd'),'inserting for oct');

1 row created.