On Thu, Apr 3, 2014 at 1:19 PM, Tom Lane <tgl@xxxxxxxxxxxxx> wrote: > Amit Langote <amitlangote09@xxxxxxxxx> writes: >> On Thu, Apr 3, 2014 at 12:54 PM, Tom Lane <tgl@xxxxxxxxxxxxx> wrote: >>> Some experimentation suggests that we are smart about "DEFAULT NULL" >>> unless the column type requires a length-coercion cast, in which >>> case the default expression involves a function call, and that doesn't >>> get elided. > >> Is there a warning about such behavior in the manual? >> Is it useful to include it somewhere (not sure where though)? > > We could just rephrase the ALTER TABLE docs to say that the table > rewrite is avoided if you omit the DEFAULT clause, rather than > saying that a null default works. > Agreed. -- Amit -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
