Have you thought about user another kind of Database, which supports volative content for example ?
I am currently thinking about doing something similar. The best and simplest option at the moment that I can think of is Redis. In redis you have the option of querying keys with wildcards. Your problem can be done by just inserting an UUID into Redis for a certain amount of time ( the best is to tailor this amount of time as an inverse function of the number of keys existing in Redis). *With Redis* What I would do : I cut down time in pieces of X minutes ( 15 minutes, for example by truncating a timestamp). Let timestampN be the timestamp for the period of time ( [N,N+15] ), let Topic1 Topic2 be two topics then : One or more people will view Topic 1 then Topic2 then again Topic1 in this period of 15 minutes (HINCRBY is the Increment) H <http://redis.io/commands/hincrby>INCRBY<http://redis.io/commands/hincrby> topics:Topic1:timestampN viewcount 1 H <http://redis.io/commands/hincrby>INCRBY<http://redis.io/commands/hincrby> topics:Topic2:timestampN viewcount 1 H <http://redis.io/commands/hincrby>INCRBY<http://redis.io/commands/hincrby> topics:Topic1:timestampN viewcount 1 Then you just query in the following way : MGET <http://redis.io/commands/mget> topics:*:timestampN * is the wildcard, you order by viewcount and you have what you are asking for ! This is a simplified version of what you should do but personnally I really like the combination of Cassandra and Redis. Victor 2011/5/18 Aditya Narayan <ady...@gmail.com> > I would arrange for memtable flush period in such a manner that the time > period for which these most viewed discussions are generated equals the > memtable flush timeperiod, so that the entire row of most viewed discussion > on a topic is in one or maximum two memtables/ SST tables. > This would also help minimize several versions of the same column in the > row parts in different SST tables. > > > > On Wed, May 18, 2011 at 11:04 PM, Aditya Narayan <ady...@gmail.com> wrote: > >> ************* >> For a discussions forum, I need to show a page of most viewed discussions. >> >> For implementing this, I maintain a count of views of a discussion & when >> this views count of a discussion passes a certain threshold limit, the >> discussion Id is added to a row of most viewed discussions. >> >> This row of most viewed discussions contains columns with Integer names & >> values containing serialized lists of Ids of all discussions whose views >> count equals the Integral name of this column. >> >> Thus if the view count of a discussion increases I'll need to move its >> 'Id' from serialized list in some column to serialized list in another >> column whose name represents the updated views count on that discussion. >> >> Thus I can get the most viewed discussions by getting the appropriate no >> of columns from one end of this Integer sorted row. >> >> ************ >> >> I wanted to get feedback from you all, to know if this is a good design. >> >> Thanks >> >> >> >> >> >> >
