ORDER BY strings (can be numbers or strings) putting empty strings last MySQL

Question

I have a problem ordering a table.

I have a column of strings. These strings can be numeric (integer).

Now I want to order by ascending, leaving numbers on top and strings at the bottom, with the empty ones last:

12
23
28
33
Hello
Hello again
(empty string)
(empty string)

This is the problem, if I go with:

ORDER BY column ASC

this happens:

(empty string)
(empty string)
12
23
28
33
Hello
Hello again

I tried with:

ORDER BY CAST(column as unsigned) ASC, column ASC/DESC

but it puts number values at the bottom:

Hello again
Hello
(empty string)
(empty string)
(empty string)
12
23
28
33

How may I solve that? Thank you very much!

Answer 1

order by 
case 
when column is null then 1 else 0 
end, 
column

OR

  ORDER BY ISNULL(column), column ASC;

OR

  ORDER BY if(column = '' or column is null,1,0),column