On Wed, Jul 29, 2009 at 01:15:27PM +0000, Jasen Betts wrote: > On 2009-07-23, Sam Mason <sam@xxxxxxxxxxxxx> wrote: > > http://www.postgres.cz/index.php/PostgreSQL_SQL_Tricks#Attention_on_IS_NULL_and_IS_NOT_NULL_operators_for_composite_types > > > > is scary; even worse is that it was changed to be like this in 8.2 > > because the standard says it should behave this way. What on earth were > > they thinking when they defined the standard this way? > > since any comparson involving those tuples will return NULL true is the > correct value for IS NULL I think you missed the point: SELECT r IS NULL, r IS NOT NULL FROM (VALUES (1,NULL)) r(a,b); returns FALSE for *both* columns. How can a row be both NULL *and* non-NULL? > if you are bothered by this behavior you are misusing NULL. I understand that this is the specified behavior, and hence PG is correctly following the spec--but it still bothers me. -- Sam http://samason.me.uk/ -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
