Re: BUG #3937: timestamp null value comparison in subquery using IN/NOT IN

"Jan Mate" <mate@yeea.eu> writes:
> Comparison between null and timestamp null value is not correct.

No, it's your expectations that are not correct.  Null is not "equal to"
null --- in fact both the queries you show will evaluate the WHERE
clause as null (unknown).

> Is there any other way to compare the subquery result (using IN or NOT IN)
> with null value?

Don't try to use null as a normal data value.  Sooner or later you'll
always regret it.

            regards, tom lane