Hey Naresh,
You asked a similar question a week or two ago. It looks like you have
simplified your needs quite a bit. Were you able to adjust your
requirements or separate the issue? You had a complicated time dimension
before, as well as a single "query" for multiple AND cases on tags.
....
> c)Give data for Metric=Sales AND Tag=U.S.A
> O/P : 5 rows
> d)Give data for Metric=Sales AND Period=Jan-10 AND Tag=U.S.A AND Tag=Pen
> O/P :1 row"
I agree with Jonathan on the model for this simplified use case. However
looking at how you are storing each partial tag combination as well as
individual tags in the partitioning key, you will be severely duplicating
your storage. You might want to just store individual keys in the
partitioning key.
Good luck,
Thunder
On Mon, Jan 27, 2014 at 8:48 AM, Naresh Yadav <nyadav....@gmail.com> wrote:
> Thanks Jonathan for guiding me..i just want to confirm my understanding :
>
> create columnfamily tagcombinations {
> partialtags text,
> tagcombinationid text,
> tagcombinationtags set<tags>
> Primary Key((partialtags), tagcombinationid)
> }
> IF i need to store TWO tagcombination TC1 as India, Pencil AND TC2 as
> India, Pen then data will stored as :
>
> TC1 TC2
> India India,Pencil India,pen
>
> TC1
> Pencil India,Pencil
>
> TC2
> Pen India,Pen
>
> TC1
> India,Pencil India,Pencil
>
> TC2
> India,Pen India, Pen
>
>
> I hope i had understood the thought properly please confirm on design.
>
> Thanks
> Naresh
>
>
> On Mon, Jan 27, 2014 at 7:05 PM, Jonathan Lacefield <
> jlacefi...@datastax.com> wrote:
>
>> 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....@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
>>>
>>>
>>
>
>
