Message-ID: <BAY175-W4881B8F05E83A4ACA02771A3CF0@phx.gbl>
From: John Lumby <johnlumby@hotmail.com>
To: postgresql docmaillist <pgsql-docs@postgresql.org>
Subject: NULL as a (pseudo-)value not described?
Date: Wed, 10 Sep 2014 17:51:32 -0400
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As far as I can tell,=A0=A0=20
the un-value NULL is not described anywhere in the doc
as being something that can be assigned to a column.

E.g. :
=A0=A0 .=A0 not listed as a constant=A0 (well that's reasonable as it isn't)
=A0=A0=A0 .=A0 not listed as an expression=A0 (is NULL an expression?)
=A0=A0=A0 .=A0 not explicitly listed under the INSERT and UPDATE commands
=A0 =A0 =A0 =A0 as a valid syntactic unit as an alternative to an expression
=A0=A0=A0=A0=A0=A0=A0 (If it is not an expression)

I do see it listed as a valid keyword but there is no description there.

To put it another way,=A0=A0 the following syntax is apparently not permitt=
ed :
=A0=A0=A0=A0=A0 UPDATE my_nullable_table SET nullable_col =3D NULL;

(I am not referring to other null-related constructs such as IS NULL,=A0 IF=
NULL etc)

I have to assume I'm missing something?
Or is it that NULL is so,=A0 well,=A0 null,=A0=A0 that it cannot be describ=
ed?

John
=20=09=09=20=09=20=20=20=09=09=20=20

--=20
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