Function Procedure Packages Oracle PLSQL Tutorial

SQL>
SQL> create or replace FUNCTION to_number_or_null(aiv_number in varchar2)return                                number is
  2  begin
  3    return to_number(aiv_number);
  4  exception
  5    when INVALID_NUMBER then
  6      return NULL;
  7  end to_number_or_null;
  8  /
Function created.
SQL>