Subject: Re: Wrong result for comparing ROW(...) with IS NOT NULL
To: Pavel Stehule <pavel.stehule@gmail.com>
Cc: PostgreSQL mailing lists <pgsql-bugs@lists.postgresql.org>
References: <21ff8e9c-627a-f949-fb00-a41b9ddcc9d3@technowledgy.de>
 <CAFj8pRAKiVUUFQawx70MXwd72rJ6D4UQFwAcmL5VVByE90HuYg@mail.gmail.com>
From: Wolfgang Walther <walther@technowledgy.de>
Message-ID: <2ba24707-e7ba-2ccb-7269-71202a400a70@technowledgy.de>
Date: Thu, 5 Nov 2020 14:40:53 +0100
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Pavel Stehule:
> for composite types this sentence is not valid
> 
> https://til.cybertec-postgresql.com/post/2019-09-29-Composite-types-and-NULL-in-PostgreSQL/
> 
> is null - is true, when all fields are null, and is not null is true, 
> when all fields is not null.

Ok, I can see how this explanation is somehow consistent. The link you 
gave is just another observation of that, though. Can I infer from 
anywhere in the official docs, that this is correct and expected behaviour?

Best

Wolfgang