You can use PADR() function.

select PADR(transform(nvl(field1,"nothing")) + ;
              transform(nvl(field2,"either")), 32) ;
  from x

>how can I set up the size for the concatenation of 2 fields within a select statement?
>
>Example:
>
>select transform(nvl(field1,"nothing")) + transform(nvl(field2,"either"))
>from x
>
>field1 and field2 are numerical. if the first row returns something like "123either", all the others will return 9 characters, if in one row i would have "nothing1234" i will actually get "nothing12". What can I do?
>
>TIA
>
>Alonso