how to identify the special character in oracle

SELECT *
  FROM <table>
 WHERE REGEXP_LIKE(<column>, '[^[:digit:]]');

 SELECT *
FROM table
WHERE regexp_like(column_name,'[^0-9]+');

  Symbol:-
=========
select * from ap_suppliers where regexp_like (VENDOR_NAME,'[#]');
select * from ap_suppliers where regexp_like (VENDOR_NAME,'[,]');

  Character:-
=========
select * from ap_suppliers where regexp_like (VENDOR_NAME,'[\z]');
select * from ap_suppliers where regexp_like (VENDOR_NAME,'[\t]');

   Number:-
=========
select * from ap_suppliers where regexp_like (VENDOR_NAME,'[1]');
select * from ap_suppliers where regexp_like (VENDOR_NAME,'[1-9]');
select * from ap_suppliers where regexp_like (VENDOR_NAME,'[1-2]');

  Table Process:-
=============

select * from special_char;

SCHAR
-------
abc$
abc
13489
kos*
289#

 select * from special_char
 where regexp_like(schar,'[^[:alnum:]]');

SCHAR
---------
abc$
kos*
289#