Hi, I am getting started with Cassandra (coming from MySQL). I have made a table with timeseries data (inspired on http://planetcassandra.org/blog/post/getting-started-with-time-series-data-modeling/ ).
The table looks like this: CREATE TABLE event_message ( message_id uuid, message_source_id uuid, message_time timestamp, event_type_id varchar, event_state varchar, filter_state varchar, image_id uuid, device_specific_id bigint, device_specific_begin_id bigint, characteristics varchar, PRIMARY KEY (message_source_id, message_time, message_id) ); I have now 2 requirements: 1) I need to remove rows after a certain (user settable) time (between 5 and 60 days). In MySQL, we used partitions by day to quickly delete a whole day. 2) I need to store a big binary file along with each row and this file should be removed when the row is removed. I was looking into the expiring columns (with the TTL), but is this a good fit for this use case? Is this TTL stored between restarts of Cassandra? Would there be any advantage to use the system called "Partitioning to limit row size – Time Series Pattern 2" in the URL and then explicitly doing a delete of a whole day? With this system, if I query by time, do I need to calculate what days are in the interval and explicitly add this in my query to find the good partitions? How can I get notifications if a row is expired when using TTL so I can removed the associated file? regards, Wim
