How to Handled this exception ORA-04054

Question

I Have the next Code and i need to handle the error when my BDlink is Down so the procedure execute eventhough this. I was using "WHEN OTHERS" but is executing always the exception bring me the worng value and it doesn't working. this procedure have to bring me one if DBLink is up and zero if Dblink is down.
declare
RETVAL NUMBER;
BEGIN
SELECT COUNT(*) INTO retval FROM [email protected];
EXCEPTION WHEN OTHERS THEN
retval := 0;
IF retval = 1 THEN
UPDATE OWNER.TABLE1 SET SELECCION = '1' WHERE CODE_AGENCY= 2;
END IF;
commit;
END;
I hope someone help me to handled ths especific Exception. I need to resolve this fast because i'm lated with this.
Thanks.

Answer 1

You are not setting the retval properly.
Try this,
DECLARE
  RETVAL   NUMBER;
BEGIN
   retval := 1;
  SELECT COUNT (*) INTO retval FROM [email protected];
  retval := 0;
EXCEPTION
  WHEN OTHERS
  THEN
    IF retval = 1
    THEN
      UPDATE OWNER.TABLE1
         SET SELECCION = '1'
       WHERE CODE_AGENCY = 2;
    END IF;
    COMMIT;
END;G.