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From Tyler Hobbs <ty...@datastax.com>
Subject Re: timezone time series data model
Date Mon, 30 Apr 2012 14:55:18 GMT
Don't use dates or datestamps as the buckets for your row keys, use a unix
timestamp modulo whatever size you want your bucket to be instead.
Timestamps don't involve time zones or any of that nonsense.

So, instead of having keys like "user1uuid_30042012", the second half would
be replaced the current unix timestamp mod 86400 (the number of seconds in
a day).

On Mon, Apr 30, 2012 at 1:46 AM, samal <samalgorai@gmail.com> wrote:

> Hello List,
>
> I need suggestion/ recommendation on time series data.
>
> I have requirement where users belongs to different timezone and they can
> subscribe to global group.
> When users at specific timezone send update to group it is available to
> every user in different timezone.
>
> I am using GroupSubscribedUsers CF where all update to group are push to
> "Each User" time line, and key is timelined by useruuid_date(one day update
> of all groups) and columns are group updates.
>
> GroupSubscribedUsers ={
>     user1uuid_30042012:{//this user belongs to same timezone
>          timeuuid1:JSON[group1update1]
>          timeuuid2:JSON[group2update2]
>          timeuuid3:JSON[group1update2]
>         timeuuid4:JSON[group4update1]
>    },
>   user2uuid_30042012:{//this user belongs to different timezone where
> date has changed already  to 1may but  30 april is getting update
>          timeuuid1:JSON[group1update1]
>          timeuuid2:JSON[group2update2]
>          timeuuid3:JSON[group1update2]
>         timeuuid4:JSON[group4update1]
>         timeuuid5:JSON[groupNupdate1]
>    },
>
> }
>
> I have noticed  this approach is good for single time zone when different
> timezone come into picture it breaks.
>
> I am thinking of like when user pushed update to group ->get user who is
> subscribed to group->check user timezone->push time series in user time
> zone. So for one user update will be on 30april where as other may have on
> 29april and 1may, using timestamps i can find out hours ago update came.
>
> Is there any better approach?
>
>
> Thanks,
>
> >>>Samal
>
>
>


-- 
Tyler Hobbs
DataStax <http://datastax.com/>

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