If you have time, this will show you how counters internally work :
http://blip.tv/datastax/counters-in-cassandra-5497678 (video from Sylvain
@CassandraSF2011)
If you just want to know what is possible to do or not with counters but
not necessary why, better read this
http://www.datastax.com/dev/b
Hi - We are struggling to understand how the counter family maintains
consistency in Cassandra.
Say Counter1 value is "1" and it is read by 2 clients at the same time who want
to update the value. After both write, it will become "3" ?