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From William R Speirs <>
Subject Re: Schema Design Question : Supercolumn family or just a Standard column family with columns containing serialized aggregate data?
Date Wed, 02 Feb 2011 15:24:16 GMT
To reiterate, so I know we're both on the same page, your schema would be 
something like this:

- A column family (as you describe) to store the details of a reminder. One 
reminder per row. The row key would be a TimeUUID.

- A super column family to store the reminders for each user, for each day. The 
row key would be something like: YYYYMMDD:user_id. The column names would simply 
be the TimeUUID of the messages. The sub column names would be the tag names of 
the various reminders.

The idea is that you would then get a slice of each row for a user, for a day, 
that would only contain sub column names with the tags you're looking for? Then 
based upon the column names returned, you'd look-up the reminders.

That seems like a solid schema to me.


On 02/02/2011 09:37 AM, Aditya Narayan wrote:
> Actually, I am trying to use Cassandra to display to users on my
> applicaiton, the list of all Reminders set by themselves for
> themselves, on the application.
> I need to store rows containing the timeline of daily Reminders put by
> the users, for themselves, on application. The reminders need to be
> presented to the user in a chronological order like a news feed.
> Each reminder has got certain tags associated with it(so that, at
> times, user may also choose to see the reminders filtered by tags in
> chronological order).
> So I thought of a schema something like this:-
> -Each Reminder details may be stored as separate rows in column family.
> -For presenting the timeline of reminders set by user to be presented
> to the user, the timeline row of each user would contain the Id/Key(s)
> (of the Reminder rows) as the supercolumn names and the subcolumns
> inside that supercolumns could contain the list of tags associated
> with particular reminder. All tags set at once during first write. The
> no of tags(subcolumns) will be around 8 maximum.
> Any comments, suggestions and feedback on the schema design are requested..
> Thanks
> Aditya Narayan
> On Wed, Feb 2, 2011 at 7:49 PM, Aditya Narayan<>  wrote:
>> Hey all,
>> I need to store supercolumns each with around 8 subcolumns;
>> All the data for a supercolumn is written at once and all subcolumns
>> need to be retrieved together. The data in each subcolumn is not big,
>> it just contains keys to other rows.
>> Would it be preferred to have a supercolumn family or just a standard
>> column family containing "all the subcolumns data serialized in single
>> column(s) " ?
>> Thanks
>> Aditya Narayan

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