Ref cursor in exception block

Question

Hi all.. I have a stored procedure that needs to return a records to Crystal Report.
I'm using an outpur parameter of type cursor.
In the proc, I am selecting the data from a table based on the input criteria and inserting into a GTT table,
if so, retrieve and store in the table and generate and throw output to CR.
if it is not returning any data i should raise exception and throw the related message to CR.
But in my proc even though it wont insert data into table b going inot next statements where it should not go.
create or replace procedure a(a1 varchar2,ref_cur out pkg1.cru)
as
cnt number;
begin
insert into b
(select * from a where a.col=a1);
commit;
open ref_cur for
select a.col from a;
EXCEPTION
WHEN OTHERS THEN
RAISE_APPLICATION_ERROR (-20001, SQLERRM);
WHEN NO_DATA_FOUND THEN
     open ref_cur for
select 'No Data Found' col from dual;
end;
1.please suggest wherer to raise exception when "select * from a where a.col=a1" doesn't return any value.
2. Can ref cursor be used in exception block.
if i use condition like
after the insert statement
select count(*) into cnt from b;
if cnt=0 then
raise NO_DATA_FOUND;
EXCEPTION
WHEN OTHERS THEN
RAISE_APPLICATION_ERROR (-20001, SQLERRM);
WHEN NO_DATA_FOUND THEN
     open ref_cur for
select 'No Data Found' col from dual;
please suggest any other way to handle
Thanks in advance

Answer 1

First and foremost some fundamental things:
EXCEPTION
WHEN OTHERS THEN
RAISE_APPLICATION_ERROR (-20001, SQLERRM);
WHEN NO_DATA_FOUND THEN
open ref_cur for
select 'No Data Found' col from dual;
end;1. You can not declare WHEN OTHERS before any other EXCEPTION. You can not compile this. Here you have declared WHEN OTHERS first then NO_DATA_FOUND and it is erroneous.
2. This is not the way you want to handle the WHEN OTHERS exception.
WHEN OTHERS_
http://tkyte.blogspot.com/2008/06/when-others-then-null-redux.html
http://tkyte.blogspot.com/2007/03/dreaded-others-then-null-strikes-again.html
http://download.oracle.com/docs/cd/E11882_01/appdev.112/e17126/toc.htm