Re: BEGIN WORK READ ONLY;

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От Joshua D. Drake
Тема Re: BEGIN WORK READ ONLY;
Дата
Msg-id 453135CD.7090102@commandprompt.com
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Ответ на Re: BEGIN WORK READ ONLY;  (Tom Lane <tgl@sss.pgh.pa.us>)
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Tom Lane wrote:
> "Joshua D. Drake" <jd@commandprompt.com> writes:
>> What is the use case for a READ ONLY transaction?
>
>> I haven't been able to come up with a good answer. Anyone got a use case
>> for this feature? I know the community didn't implement it for giggles.
>
> No, we implemented it because it's required by the SQL spec.
>
> I'm not too sure about use-cases either.  It certainly seems pretty
> useless from a protection standpoint.  It might be that some other
> DBMSes like to know about READ ONLY so they can optimize transaction
> processing, but Postgres doesn't care.  (We do the equivalent optimization
> by noting at COMMIT time whether you actually made any DB changes,
> which we can determine basically for free by seeing if the xact emitted
> any WAL records ...)

Thank you, that's what I needed.

Sincerely,

Joshua D. Drake




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