Oracle sql order by with character in order

Question

Good day, Maybe someone can help me , i want to get n select output on oracle sql , but when i order by it is not correct.

code_order
1.
2.
2.1
3.
4.2
10.1
10.0
21.
21.1
23.
31.

it needs to be ordered numeric and all values has a full stop in .

any ideas??

Thanx, but i see that some values can contain non numeric values as well like C,B etc.

1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 7C. 40. 50. 51. 6.

Table outline :

code_order is varchar2

Answer 1

使用order by to_number(code_order)

Answer 2

    with
    val as
    (
      SELECT '1.' as c FROM dual
      union all
      SELECT '2.' as c FROM dual
      union all
      SELECT '3.' as c FROM dual
      union all
      SELECT '2.1' as c FROM dual
      union all
      SELECT '4.2' as c FROM dual
      union all
      SELECT '10.1' as c FROM dual
      union all
      SELECT '21.' as c FROM dual
      union all
      SELECT '10.0' as c FROM dual
      union all
      SELECT '21.1' as c FROM dual
      union all
      SELECT '23.' as c FROM dual
      union all
      SELECT '31.' as c FROM dual
    )
SELECT c FROM val
order by to_number(regexp_replace(c, '^(\d+)\..*$', '\1'))
    ;