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From Peter Lin <wool...@gmail.com>
Subject Re: Documentation of batch statements
Date Tue, 03 Mar 2015 23:08:25 GMT
I agree with jonathan haddad. A traditional ACID transaction following the
classic definition, isolation is necessary. Having said that, there is
different levels of isolation.

http://en.wikipedia.org/wiki/Isolation_%28database_systems%29#Isolation_levels

Saying the distinction is pendantic is wrong in my bias opinion. These are
well established terms that have been around for over 2 decades. Just
because lots of programmers don't bother to understand the distinction,
doesn't make it any less important.



On Tue, Mar 3, 2015 at 5:56 PM, Jonathan Haddad <jon@jonhaddad.com> wrote:

> This is often a confusing topic because someone came up with the term
> ACID, which lists isolation as well as atomicity, and as a result most
> people assume they are independent.  This is incorrect.  For something to
> be atomic, it actually requires isolation.
>
> "An operation is atomic if no intermedia states can be observed.  It seems
> to jump directly from the initial state to the result state."
> - Concepts, Techniques, and Models of Computer Programming By Peter
> Van-Roy, Seif Haridi
>
>
>
>
> On Tue, Mar 3, 2015 at 2:30 PM Tyler Hobbs <tyler@datastax.com> wrote:
>
>>
>> On Tue, Mar 3, 2015 at 2:39 PM, Jonathan Haddad <jon@jonhaddad.com>
>> wrote:
>>
>>> Actually, that's not true either.  It's technically possible for a batch
>>> to be partially applied in the current implementation, even with logged
>>> batches.  "atomic" is used incorrectly here, imo, since more than 2 states
>>> can be visible, unapplied & applied.
>>
>>
>> That's a matter of isolation, not atomicity.  Although, with a long
>> enough gap between partial and full application, the distinction becomes
>> somewhat pedantic, I suppose.
>>
>>
>> --
>> Tyler Hobbs
>> DataStax <http://datastax.com/>
>>
>

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