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From A J <s5a...@gmail.com>
Subject Re: Does the 'batch' order matter ?
Date Wed, 14 Mar 2012 16:50:31 GMT
hmm....not sure I understand.
Are you saying the way 'batch mutate' is coded, the order of writes in
the batch does not mean anything ? You can ask the batch to do A,B,C
and then D in sequence; but sometimes Cassandra can end up applying
just C and A,B (and D) may still not be applied ?

Thanks.


On Wed, Mar 14, 2012 at 3:37 AM, aaron morton <aaron@thelastpickle.com> wrote:
> It may, but it would not be guaranteed.
>
> Cheers
>
> -----------------
> Aaron Morton
> Freelance Developer
> @aaronmorton
> http://www.thelastpickle.com
>
> On 14/03/2012, at 8:11 AM, A J wrote:
>
> I know batch operations are not atomic but does the success of a write
> imply all writes preceeding it in the batch were successful ?
>
> For example, using cql:
> BEGIN BATCH USING CONSISTENCY QUORUM AND TTL 8640000
>  INSERT INTO users (KEY, password, name) VALUES ('user2',
> 'ch@ngem3b', 'second user')
>  UPDATE users SET password = 'ps22dhds' WHERE KEY = 'user2'
>  INSERT INTO users (KEY, password) VALUES ('user3', 'ch@ngem3c')
>  DELETE name FROM users WHERE key = 'user2'
>  INSERT INTO users (KEY, password, name) VALUES ('user4',
> 'ch@ngem3c', 'Andrew')
> APPLY BATCH;
>
> Say the batch failed but I see that the third write was present on a
> node. Does it imply that the first insert and the second update
> definitely made to that node as well ?
>
> Thanks.
>
>

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