Oracle Error 0 appears when creating cursor

[Agnus]

Hi,
In a rather large form, I'm trying to make a new procedure. All is well until I add the cursor, and then it won't compile. The cursor works fine in SQLPlus, but forms won't compile it - I get Error 0 at line 0(!).

The cursor is something like this:

Cursor c1 is
SELECT ta.trans_id, ta.seq_no
FROM table_a ta, table_b tb
WHERE ta.text1 = tb.text1 -- these are the standard joins
and to_number(ta.action) = tb.code --
and tb.type = 'X'
and ta.trans_id <= (select(max(ta1.trans_id))
from table_a ta1
where ta1.trans_id = ta.trans_id);

- don't worry about the names i've used, and the subquery is a standard one we use here to find the latest
transaction. Anyway, does anyone know anything more about this Error 0? I don't think the form is too big,
as I managed to make another procedure of about the same size, then delete it before starting
this one. What else could Error 0 be alluding to?
thanks in advance ...

 

[Agnus]

Found an easy/dirty way to avoid this:
Don't use the cursor! one of the joys(?) of pl/sql is that there's many ways to do the same thing. I relaised I could use a select into instead of a cursor fetch, and the error vanished. Still no idea why it appeared in the first place though. ho hum.