Re: BUG #16862: Unexpected result of checking for null "IS NOT NULL" in function

=?UTF-8?B?0JTQvNC40YLRgNC40Lkg0JjQstCw0L3QvtCy?= <firstdismay@gmail.com> writes:
> Does not work means does not produce the expected result. It seemed
> obvious to me.

If it were obvious I wouldn't be asking you for more information.
You've left out a lot, like the table details and any sample data
that might be necessary to reproduce the problem.

The link I sent you offers some suggestions about how to create
a self-contained problem report.  Ideally, provide a SQL script
that anyone can run in an empty database to see the misbehavior.

Also, please keep the mailing list cc'd.  I'm not the only
developer who might take an interest in this problem, once
we understand what it is.

            regards, tom lane