Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1Ym4te-00081u-VJ for pgsql-docs@arkaria.postgresql.org; Sat, 25 Apr 2015 18:33:47 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1Ym4te-0004ck-61 for pgsql-docs@arkaria.postgresql.org; Sat, 25 Apr 2015 18:33:46 +0000 Received: from makus.postgresql.org ([2001:4800:1501:1::229]) by malur.postgresql.org with esmtps (TLS1.2:RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1Ym4td-0004ce-Bd for pgsql-docs@postgresql.org; Sat, 25 Apr 2015 18:33:45 +0000 Received: from mail-ie0-x234.google.com ([2607:f8b0:4001:c03::234]) by makus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.84) (envelope-from ) id 1Ym4tW-0004FM-EM for pgsql-docs@postgresql.org; Sat, 25 Apr 2015 18:33:44 +0000 Received: by iedfl3 with SMTP id fl3so116812787ied.1 for ; Sat, 25 Apr 2015 11:33:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=gnXa1uZF3mz/2pLwZ6+Dp92QdKr3BvTr9tewiB3y5s4=; b=IA7+MEp2YoTwF5nfNXVgnAchLyMtZh8uGv8MjOqXN2j2mIBZE8AvB1P97j+bHYasGa GOWQkz/qxMB0VO/bHnv93Z32CSUZaQEjtmIEdyr5XRZ7NbexhF91dxDjW7lAX4PFIU7j xrH9OrcoSder5CPYhuIM4nAySFUumDEPd64v0mAfi5xGdgS2Seyr/29LxQWXDjHNKe+V fESgoryah5LcK6RtYSCgMEAQWOBllh5SmT6Jy1pJq6HLNe3cRNFDaogBbo6JslNFxshk ByxjgX9duEaBAbrVyzwAT4qRDkulX9srg5M44BTQIIpSlBsPIihP8xAvHEoSbgs5+gpB YRFA== MIME-Version: 1.0 X-Received: by 10.107.165.206 with SMTP id o197mr5060809ioe.56.1429986816981; Sat, 25 Apr 2015 11:33:36 -0700 (PDT) Received: by 10.36.64.15 with HTTP; Sat, 25 Apr 2015 11:33:36 -0700 (PDT) In-Reply-To: <20150425180249.GA17791@momjian.us> References: <1691752982.3879494.1429908040587.JavaMail.yahoo@mail.yahoo.com> <20150425180249.GA17791@momjian.us> Date: Sat, 25 Apr 2015 11:33:36 -0700 Message-ID: Subject: Re: Add a new table for Transaction Isolation? From: "David G. Johnston" To: Bruce Momjian Cc: Kevin Grittner , Peter Eisentraut , "pgsql-docs@postgresql.org" Content-Type: multipart/alternative; boundary=001a11415074427f45051490c09e X-Pg-Spam-Score: -2.7 (--) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-docs Precedence: bulk Sender: pgsql-docs-owner@postgresql.org --001a11415074427f45051490c09e Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Sat, Apr 25, 2015 at 11:02 AM, Bruce Momjian wrote: > On Fri, Apr 24, 2015 at 08:40:40PM +0000, Kevin Grittner wrote: > > And, for reasons given above, I really question whether such a > > table doesn't do more harm than good. Even those citing the paper > > by Berenson, et al., often miss the text in *that* paper about what > > the actual definition of serializable transactions in the standard > > is, and instead focus on the quick-to-read tables of how the > > misinterpretation of serializable transactions based on the > > standard's table of phenomena (which the paper dubs "ANOMALY > > SERIALIZABLE") differs from truly serializable behavior. > > > > People do love tables like this, which makes providing them > > tempting; but when a short, clean table is available they often > > seem less inclined to take the trouble to read the real information > > the table summarizes -- and they come away with distorted and > > incorrect ideas about the subject matter. > > I don't think we can abandon the table --- people have enough trouble > figuring this out, including me, and without the table, it will be even > harder. > > What I have done is to add two rows and one column to the table, and > changed the surrounding text to more clearly reference the table. You > can see the output here, and the SGML patch is attached: > > http://momjian.us/expire/transaction-iso.html Need to add "Serialization Anomalies" to the previous section's definitions list. =E2=80=8BPondering whether something like: "Possible (not in PG)" and avoid= ing the additional rows would make reading the table easier. David J. --001a11415074427f45051490c09e Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
On Sat, Ap= r 25, 2015 at 11:02 AM, Bruce Momjian <bruce@momjian.us> wrote:
On Fri, Apr 24, 2015 at = 08:40:40PM +0000, Kevin Grittner wrote:
> And, for reasons given above, I really question whether such a
> table doesn't do more harm than good.=C2=A0 Even those citing the = paper
> by Berenson, et al., often miss the text in *that* paper about what > the actual definition of serializable transactions in the standard
> is, and instead focus on the quick-to-read tables of how the
> misinterpretation of serializable transactions based on the
> standard's table of phenomena (which the paper dubs "ANOMALY<= br> > SERIALIZABLE") differs from truly serializable behavior.
>
> People do love tables like this, which makes providing them
> tempting; but when a short, clean table is available they often
> seem less inclined to take the trouble to read the real information > the table summarizes -- and they come away with distorted and
> incorrect ideas about the subject matter.

I don't think we can abandon the table --- people have enough tr= ouble
figuring this out, including me, and without the table, it will be even
harder.

What I have done is to add two rows and one column to the table, and
changed the surrounding text to more clearly reference the table.=C2=A0 You=
can see the output here, and the SGML patch is attached:

=C2=A0 =C2=A0 =C2=A0 =C2=A0 http://momjian.us/expire/transaction-iso.html<= /a>

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