On Thu, Nov 17, 2011 at 2:36 PM, RobinUs2 <ro...@us2.nl> wrote: > We're currently developing a system with a time tracking part. We need to > store following details: > - user > - time (in minutes) > - description > - billable > - project > - task ID > > What would be a proper data structure for this in Cassandra?
How do you need to be able to query the data? Specific details matter. For example, do you just need to know what happened for a specific user during a given time period? Or do you need to know what happened across all users during a given time period? All users of a given project? These details matter because in Cassandra you tend to have one column family per type of query that you need to be able to answer efficiently (i.e. in real time). Ad-hoc queries aren't efficient on large, distributed data sets like you tend to use Cassandra for; you need to know what your reads will look like to know how to model your data. -- Tyler Hobbs DataStax <http://datastax.com/>
