APEX

Hi

Question is: How to maintain PLSQL exception in application.

first example:
Suposse I have procedure:

..........
begin
.........
select col_one into v_col_one from table
where col_two = value;

exception

when no_data_found then
raise_application_error (-20001, 'Error....');

when too_many_rows then
raise_application_error (-20002, 'Error....');
end;


second example:

..........
my_exception exception;
begin
.........
update table
set col_one = value_one
where col_two = value_two;

if sql%rowcount = 0 then
raise my_exception;

exception
when my_exception then
/* to do */
end;

I would like to send message on the page to input correct values.