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From Jonathan Lacefield <jlacefi...@datastax.com>
Subject Re: Help me on Cassandra Data Modelling
Date Mon, 27 Jan 2014 13:35:40 GMT
Hello,

  The trick with this data model is to get to partition based, and/or
cluster based access pattern so C* returns results quickly.  In C* you want
to model your tables based on your query access patterns and remember that
writes are cheap and fast in C*.

  So, try something like the following:

  1 Table with a Partition Key = Tag String
         Tag String = "Tag" or "set of Tags"
         Cluster based on tag combination (probably desc order)
         This will allow you to select any combination that includes Tag or
"set of Tags"
         This will duplicate data as you will store 1 tag combination in
every Tag partition, i.e. if a tag combination has 2 parts, then you will
have 2 rows

  Hope this helps.

Jonathan Lacefield
Solutions Architect, DataStax
(404) 822 3487
<http://www.linkedin.com/in/jlacefield>


<http://www.datastax.com/what-we-offer/products-services/training/virtual-training>


On Mon, Jan 27, 2014 at 7:24 AM, Naresh Yadav <nyadav.ait@gmail.com> wrote:

> Hi all,
>
> Urgently need help on modelling this usecase on Cassandra.
>
> I have concept of tags and tagcombinations.
> For example U.S.A and Pen are two tags AND if they come together in some
> definition then register a tagcombination(U.S.A-Pen) for that..
>
> *tags *(U.S.A, Pen, Pencil, India, Shampoo)
> *tagcombinations*(U.S.A-Pen, India-pencil, U.S.A-Pencil, India-Pen,
> India-Pen-Shampoo)
>
> - millions of tags
> - billions of tagcombinations
> - one tagcombination generally have 2-8 tags....
> - Every day we get lakhs of new tagcombinations to write
>
> Query need to support :
> one tag or set of tags appears in how many tagcombinationids ????
> If i query for Pen,India then it should return two tagcombinaions
> (India-Pen, India-Pen-Shampoo))..Query will be fired by application in
> realtime.
>
> I am new to cassandra and need to deliver fast so please give your inputs.
>
> Thanks
> Naresh
>
>

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