Message-ID: <13f52b5d04f64804096bca4f2467caacdc199137.camel@cybertec.at>
Subject: Re: is_nullable column of information_schema.columns table
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: mdemir4527@gmail.com, pgsql-docs@lists.postgresql.org
Date: Tue, 07 Jan 2020 11:41:29 +0100
In-Reply-To: <157756439102.1159.4361947883550826524@wrigleys.postgresql.org>
References: <157756439102.1159.4361947883550826524@wrigleys.postgresql.org>
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On Sat, 2019-12-28 at 20:19 +0000, PG Doc comments form wrote:
> Page: https://www.postgresql.org/docs/12/infoschema-columns.html
> Description:
> 
> is_nullable column of information_schema.columns table does not show correct
> values for columns of views. For tables that column shows correct values
> whether a column is nullable or not. I think the documentation should
> include this information although better solution is to correct that error.

All columns of a view are defined as nullable, whether they can assume
that value or not.  PostgreSQL does not attempt to deduce the nullability
of columns from the view definition.

So the information in information_schema.columns is correct.
Remember that nullability does not imply that there are actually NULL values.

Yours,
Laurenz Albe
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