There was a by here last year who did something similar and did a nice write up. Cannot find it right now, some googleing may help.
Aaron On 16/02/2011, at 2:56 AM, Victor Kabdebon <victor.kabde...@gmail.com> wrote: > Hello Sasha. > > In this sort of real time application the way you insert (QUORUM, ONE, etc..) > and the way you retrieve is extremely important because your data may not > have had the time to propagate to all your nodes. Be sure to use adequate > policies to do that : insert to a certain number of nodes but don't sacrifice > to much time doing that to keep the real time component. > Here is a presentation of how the chat is made in Facebook, it may be useful > to you : > > http://www.erlang-factory.com/upload/presentations/31/EugeneLetuchy-ErlangatFacebook.pdf > > It's more focused on erlang, but it might give you ideas on how to deal with > that problem (I am not sure that DB are the best way to deal with that... but > it's just my opinion). > > Victor Kabdebon > http://www.voxnucleus.fr > > > > 2011/2/15 Sasha Dolgy <sdo...@gmail.com> > thanks for the response. thinking about this, this would not allow for the > sorting of messages into a chronological order for end user display. i had > thought about having each message as its own column against the room or the > user, but i have had some inconsistencies in retrieving the data. sometimes > i get 3 columns, sometimes i get 50...( i think this is because of the random > partitioner) > > i had thought about this structure: > > [messages][nickname][message id => message data] > [chatrooms][room_name][message id] > > this way i can pull all messages a user ever posted, not specific to a room. > what i haven't been able to do so far is print the timestamp on the row or > column. does this have to be explicitly added somewhere or can it be > returned as part of a 'get' request? > > -sd > > > On Tue, Feb 15, 2011 at 2:12 PM, Michal Augustýn <augustyn.mic...@gmail.com> > wrote: > The schema design depends on chatrooms/users/messages numbers. I.e. you can > have one CF, where key is chatroom, column name is username, column value is > the message and message time is the same as column timestamp. > You can add day-timestamp to the chatroom name to avoid large rows. > > Augi > > 2011/2/15 Andrey V. Panov <panov.a...@gmail.com> > > I never did it. But I suppose you can use "chatroom name" as key and store > messages & nicks as columns in JSON and timestamp as columnName. > > > > > -- > Sasha Dolgy > sasha.do...@gmail.com >
