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From: Greg Sabino Mullane <htamfids@gmail.com>
Date: Wed, 25 Sep 2024 16:49:34 -0400
Message-ID: <CAKAnmmL05Lt89EOnMW111qdUOau+dYG7u8ff5o+ckKKohnNwGg@mail.gmail.com>
Subject: Re: Repeatable Read Isolation Level "transaction start time"
To: Ron Johnson <ronljohnsonjr@gmail.com>
Cc: "pgsql-generallists.postgresql.org" <pgsql-general@lists.postgresql.org>
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>
> Since transactions should be "as short as possible, without being too
>> short", how much time is there between when you run "BEGIN;" and the first
>> "work statement"?
>>
>
I don't know that it really matters. For something automated, it would be a
few milliseconds. Either way, I'm sure most people/apps already think of
the initial 'BEGIN ...' as the start of the transaction, and act
accordingly.

Maybe long-term something like

BEGIN   ISOLATION MODE REPEATABLE READ   SNAPSHOT NOW;

could be useful.

Cheers,
Greg

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<div dir=3D"ltr"><div class=3D"gmail_quote"><blockquote class=3D"gmail_quot=
e" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204)=
;padding-left:1ex"><div dir=3D"ltr"><div class=3D"gmail_quote"><blockquote =
class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px sol=
id rgb(204,204,204);padding-left:1ex"><div dir=3D"ltr"><div class=3D"gmail_=
quote">Since transactions should be &quot;as short as possible, without bei=
ng too short&quot;, how much time is there between when you run &quot;BEGIN=
;&quot; and the first &quot;work statement&quot;?</div></div></blockquote><=
/div></div></blockquote><div><br></div><div>I don&#39;t know that it really=
 matters. For something automated, it would be a few milliseconds. Either w=
ay, I&#39;m sure most people/apps already think of the initial &#39;BEGIN .=
..&#39; as the=C2=A0start of the transaction, and act accordingly.</div><di=
v><br></div><div>Maybe long-term something like</div><div><br></div><div>BE=
GIN=C2=A0 =C2=A0ISOLATION MODE REPEATABLE READ=C2=A0 =C2=A0SNAPSHOT NOW;</d=
iv><div><br></div><div>could be useful.</div><div><br></div><div>Cheers,</d=
iv><div>Greg</div><div><br></div><div><br></div></div></div>

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