Yon Den Baguse Ngarso <yon(at)dugem(dot)com> writes:
> If i create tbl1 & tbl2, and then load it with the data.
> The result is CORRECT. Like yours.
> But, if the data loaded from another table, the result become WRONG/ null record.
Do you have any nulls in what you are selecting into tbl2?
The behavior of NOT IN with nulls is not very intuitive.
regards, tom lane