Received: from malur.postgresql.org ([2a02:16a8:dc51::56]) by arkaria.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.89) (envelope-from ) id 1gBvva-0005xC-0n for pgsql-docs@arkaria.postgresql.org; Mon, 15 Oct 2018 06:00:30 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.89) (envelope-from ) id 1gBvvX-0006O2-KT for pgsql-docs@arkaria.postgresql.org; Mon, 15 Oct 2018 06:00:27 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.89) (envelope-from ) id 1gBvvX-0006Nv-6Y for pgsql-docs@lists.postgresql.org; Mon, 15 Oct 2018 06:00:27 +0000 Received: from mail-qt1-x831.google.com ([2607:f8b0:4864:20::831]) by magus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.89) (envelope-from ) id 1gBvvQ-0008Sy-JR for pgsql-docs@lists.postgresql.org; Mon, 15 Oct 2018 06:00:26 +0000 Received: by mail-qt1-x831.google.com with SMTP id c56-v6so20218722qtd.11 for ; Sun, 14 Oct 2018 23:00:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=Q+E0Z9yoWKexXWa08HGiTaid25K9+5Ls8aHzI/UJEuE=; b=iL7Xqz2UlGafYfpsrF4w+xtunAsAjQLmmasKk4wK8Ci570WfkvIVoXRqScIvKV1b38 JonSPrr5daMVUrnS9W4KxjvCmKb0T66Twj3PkPdQdcVhhNHiFPoogoIqCMewr9IZj7z7 rkegNw4uu2DtzMRCXmgiaTJH9sezeb5bXDDwWx04Juz1URWoNVyBjMsyHUho9Jb2Fzxb zC4ZaJtsRdlHyRyiHJk9+rx0jM2zPrXP1CGEAGrRj0m6+G5hWW51JyX8+lk0FdDrg8Vo s8oVwAVwge1ERjXCab2c4cuQpw3dTBa2TffvGK3HFbTH1ObnKO6N0JcXWK2NW0Ih3Yx3 4lvQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=Q+E0Z9yoWKexXWa08HGiTaid25K9+5Ls8aHzI/UJEuE=; b=TPm/3X6CZjQGEwq0aPQ31U4ovnv6a5M9BR0WP8EpGHCnP6hpIgcx1YUb8td1Heec9L SKcWVW7BVOcoORae5uHF+FaCI54nOpH391BBQj299l3Zbfm7+7o9sOZuRzZIbZa3PK0e RJ9LLQKyVJgz+TXPyv4a3DhJwuy0xulNIu8ajAF7P3O1lIz5wchVRU9H30rIl6sFcESV JE7Sayxmwpi7CS+w8jd17UXpmO31rOIhozev92WbM/MZYgm3WRx5KjXUyknWriU5rFsu zZaVbIKf7EGpUl0GhbT5B0kzrri9C1jZ3ZUfzNn1OwDxUHlHak5iHf+vB7dgfkdJ1fJU q/6w== X-Gm-Message-State: ABuFfohu8L6pN9iOwkdXyB9gfqflr7rCA53AwLJTpJrWz7nys3QHuA6Z TbkM6M7mNnIO/c0TYj5IC1tgdBh/1Q1w3d8FSTvtTA== X-Google-Smtp-Source: ACcGV61Iiny/GX3tGBU21VNdnc82zRh0GGMQ2M11zi5ZsPE1MqmgqanoGDvM/tI2Ny96L8YI/9Bqh4VWR/6oIqdMxSE= X-Received: by 2002:ac8:39c5:: with SMTP id v63-v6mr15118517qte.273.1539583219013; Sun, 14 Oct 2018 23:00:19 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:a0c:b50b:0:0:0:0:0 with HTTP; Sun, 14 Oct 2018 23:00:18 -0700 (PDT) In-Reply-To: <20181013173148.GA25417@momjian.us> References: <153701242703.22334.1476830122267077397@wrigleys.postgresql.org> <20181011210934.GG7807@momjian.us> <5831541539340923@iva8-3af116a85b74.qloud-c.yandex.net> <20181012150433.GA12966@momjian.us> <1806231539422738@sas1-00d5718ef836.qloud-c.yandex.net> <20181013173148.GA25417@momjian.us> From: "David G. Johnston" Date: Sun, 14 Oct 2018 23:00:18 -0700 Message-ID: Subject: Re: Ambiguous usage of 'any' in explanation To: Bruce Momjian Cc: KES , "pgsql-docs@lists.postgresql.org" Content-Type: multipart/alternative; boundary="000000000000df1b8d05783e2642" List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk --000000000000df1b8d05783e2642 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Saturday, October 13, 2018, Bruce Momjian wrote: > On Sat, Oct 13, 2018 at 12:25:38PM +0300, KES wrote: > > >or NULL if any of the comparisons result in unknown > > result in unknown?? > > Well, SQL has a three-valued logic, and UNKOWN values are treated like > NULL. For me they have always been the same, and I would like to avoid > "unknown" in this context, if possible. > > I was just trying to avoid using the word null twice in the same sentence but it=E2=80=99s not a strong aversion. David J. --000000000000df1b8d05783e2642 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Saturday, October 13, 2018, Bruce Momjian <bruce@momjian.us> wrote:
On Sat, Oct 13, 2018 at 12:25:38PM +0300, KES wrote:
> >or NULL if any of the comparisons result in unknown
> result in unknown??

Well, SQL has a three-valued logic, and UNKOWN values are treated like
NULL.=C2=A0 For me they have always been the same, and I would like to avoi= d
"unknown" in this context, if possible.


I was just trying to avoid using the word = null twice in the same sentence but it=E2=80=99s not a strong aversion.

David J.

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