Hi all,

    I was hoping you could provide some assistance with a data modeling question (my apologies if a similar question has already been posed).  I have time based data that I need to store on a per customer (aka app id ) basis so that I can easily return it in sorted order by event time.  The data in question is being written at high volume (~50K / sec) and I am concerned about the cardinality of using either app id or event time as the row key as either will likely result in hot spots.  Here are is the table definition I am considering:

create table organic_events (
event_id UUID,
app_id INT,
event_time TIMESTAMP,
user_id INT,
PRIMARY KEY (app_id, event_time, event_id)
)  WITH CLUSTERING ORDER BY (app_id asc,event_time desc);

So that I can be able to query as follows which will naturally sort the results by time descending:  

select * from organic_events where app_id = 1234 and event_time <= '2012-01-01' and event_time > '2012-01-01';

Anyone have an idea of the best way to accomplish this?  I was considering the following: