Data Type Oracle PLSQL

SQL>
SQL> -- Convert the string to a number and pass the format string $99,999.99 to TO_NUMBER():
SQL>
SQL> SELECT TO_NUMBER('-$12,345.67', '$99,999.99') FROM dual;
TO_NUMBER('-$12,345.67','$99,999.99')
-------------------------------------
                            -12345.67
SQL>
SQL>
SQL>