如何在不使用regexp_like的情况下从列中获取整数

SQL> with test as
2    (select 'a1b2c3' col from dual union all
3     select 'abc'        from dual union all
4     select '1ab'        from dual union all
5     select '123'        from dual union all
6     select '156-346'    from dual
7    )
8  select col,
9    regexp_replace(col, '[^[:digit:]]') result,
10    --
11    translate(col, '0'|| translate(col, '$0123456789', '$'), '0') result2
12  from test;
COL     RESULT  RESULT2
------- ------- -------
a1b2c3  123     123
abc
1ab     1       1
123     123     123
156-346 156346  156346
SQL>

select x
from test
where trim(translate(x, '0123456789', '          ')) is null;

select x
from test
where trim(translate(replace(x,' ','*'), '0123456789', '          ')) is null;