Eliminating special characters from a value or Finding values with special characters

Query to Eliminate special characters from a column value:

          select translate('e%rerA%' , 'A(%$*&@,;''/+-' , 'A') from dual;

Query to retrieve only the special characters from the column value:


select  translate(string_column,'%' || translate(string_column,'X(%$*&@,;''/+-)','X'),'%') special_characters
  from  (select 'test%er'  string_column from dual);

Query to select only the rows whose column values has the special characters:


  SELECT string_column FROM (select 'test%er'  string_column from dual)
  WHERE string_column != nvl(translate(string_column , 'A(%$*&@,;''/+-' , 'A'), 'A');