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From: "Hiller, Dean" <Dean.Hiller@nrel.gov>
To: "user@cassandra.apache.org" <user@cassandra.apache.org>,
	"cbertu81@libero.it" <cbertu81@libero.it>
Date: Wed, 9 Oct 2013 11:48:51 -0600
Subject: Re: Online shop with Cassandra
Thread-Topic: Online shop with Cassandra
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Message-ID: <CE7AF2B8.32FCE%Dean.Hiller@nrel.gov>
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Read the paper "Building on Quicksand"  especially the section where he
describes what they do at Amazon=8Athe apology model=8Aie. Allow overbookin=
g
and apologize but limit overbooking=8A.That is one way to go and stay
scalable.

You may want to analyze the percentage change that overbooking can be as
well=8A..the paper may give you other ideas.

Another idea is atomic row update and leveraging that which I think is in
2.0 such that the first person wins.

Later,
Dean

On 10/9/13 9:59 AM, "cbertu81@libero.it" <cbertu81@libero.it> wrote:

>Hi all,
>for an online shop owned by my company I would like to remove MySQL for
>everything concerning the frontend and use Cassandra instead.
>The site has more than a million visit each day but what we need to know
>is
>
>Products (deals) are divided for cities
>Each product can stay online for X time and sell a max number of Y items
>
> CREATE TABLE deals (
>        city string,
>        deal_id timeuuid,
>        availability int,
>        deal_info string,
>        PRIMARY KEY ((city, deal_id))
>    );
>
>The only problem I see in this model is how to guarantee the
>"availability" of=20
>a deal and don't "overbook" -- How to solve the problem of "remaining
>items" in=20
>real time?=20
>
>I have many idea how to solve it on the web-application but I wonder if
>there=20
>is nothing ready on Cassandra that might help.
>
>Kindest regards,
>Carlo
>