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From Victor Kabdebon <victor.kabde...@gmail.com>
Subject Re: unique key generation
Date Tue, 08 Feb 2011 04:40:35 GMT
It depends on the way you generate your UUID.

Here is a random and very efficient way to generate UUID with a good package
:

http://johannburkard.de/software/uuid/

Best regards,
Victor Kabdebon
http://www.voxnucleus.fr

2011/2/7 Kallin Nagelberg <kallin.nagelberg@gmail.com>

> Pretty sure it also uses mac address, so chances are very slim. I'll check
> out time uuid too, thanks.
>
> On 7 Feb 2011 17:11, "Victor Kabdebon" <victor.kabdebon@gmail.com> wrote:
>
> Hello Kallin.
> If you use timeUUID the chance to generate two time the same uuid is the
> following :
> considering that both client generate the uuid at the *same millisecond*,
> the chance of generating the same uuid is :
>
> 1/1.84467441 × 1019Which is equal to the probability for winning a
> national lottery for 1e11 days in a row ( for 270 million years).
> Well if you do have a collision you should play the lottery :).
>
> Best regards,
> Victor Kabdebon
> http://www.voxnucleus.fr
>
> 2011/2/7 Kallin Nagelberg <kallin.nagelberg@gmail.com>
>
>
> >
> > Hey,
> >
> > I am developing a session management system using Cassandra and need
> > to generate uni...
>
>

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