ALTER SESSION SET CURRENT_SCHEMA = HR;

BEGIN
 EXECUTE IMMEDIATE 'DROP TABLE mytable';
EXCEPTION
 WHEN OTHERS THEN
 IF SQLCODE != -942 THEN
   RAISE;
 END IF;
END;

create table mytable (
num int not null primary key,
nominativo varchar(50));
set serveroutput on
 
insert into mytable values(1,'Tizio Caio');
insert into mytable values(6,'Caio Duilio');
begin
 insert into mytable values(2,'Paolo Rossi');
 insert into mytable values(15,'Nicola Tux');
 insert into mytable values(1,'Nicola Tux');
exception
 when dup_val_on_index then
 dbms_output.put_line('Attenzione oops:' || sqlerrm);
 rollback;
end;

select * from mytable;

commit;

— Divide by zero

DECLARE v_invalid PLS_INTEGER;
BEGIN
v_invalid := 100/0;
EXCEPTION
WHEN ZERO_DIVIDE THEN
DBMS_OUTPUT.PUT_LINE (‘attenzione il risultato è in errore (divide by 0)’);
END;