"David G. Johnston" <david.g.johns...@gmail.com> writes: > The concept embodied by "NULL" in the operator "IS [NOT] NULL" is distinct > from the concept embodied by "NULL" in the operator "IS [NOT] DISTINCT > FROM".
> In short, the former smooths out the differences between composite and > non-composite types while the later maintains their differences. While a > bit confusing I don't see that there is much to be done about it - aside > from making the distinction more clear at: > âhttps://www.postgresql.org/docs/devel/static/functions-comparison.html > Does spec support or refute this distinction in treatment? AFAICS, the IS [NOT] DISTINCT FROM operator indeed is specified to do the "obvious" thing when one operand is NULL: you get a simple nullness check on the other operand. So I went ahead and documented that it could be used for that purpose. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
