yamt@mwd.biglobe.ne.jp (YAMAMOTO Takashi) writes:
> how about making heap_form_tuple and its variants use smaller natts for
> tuples whose trailing columns are NULL?
This idea has been proposed before, and rejected on the basis that it's
unlikely to save enough to be worth the cycles needed to check for the
case. Keep in mind that you aren't going to save anything at all unless
the bitmap length decreases across a MAXALIGN boundary.
regards, tom lane