It's unpredictable, there could be hundreds of thousands, even millions (but unlikely).
How many total ranges to you expect to have long term?
On Tue, Nov 1, 2011 at 11:17 AM, Tamas Marki <firstname.lastname@example.org> wrote:
> I'm new to the list and also to Cassandra. I found it when I was searching
> for something to replace our busy mysql server.
> One of the things we use the server for is filtering IPs based on a list of
> IP ranges. These ranges can be small and big, and there are about 50k of
> them in the database.
> In mysql this is pretty quick: they are stored as integers, and the query
> basically looks like (say ip is the ip we want to find the all the ranges
> select range from rangelist where ip_start<=ip and ip_end>=ip;
> I tried to move this schema to Cassandra, but it turned out to be very slow,
> even with indexes on both columns. Since I also had to have an EQ expression
> in the query, I added an indexed text field which was the same for all rows,
> so the query in cassandra was something like this:
> select range from rangelist where type='ip' and ip_start<=ip and ip_end>=ip;
> This was very slow, and I imagine it is because it has to scan through all
> the rows, making the index useless.
> The second thing I tried was to just expand the ranges and store individual
> IPs as the keys to a column family. This is very fast to query, but the
> problem is that I now have over 2.7 million rows, because some of the ranges
> are quite large.
> As the number of ranges could change, this method could be a problem -
> imagine we add a whole A-class range, it would explode into millions of
> My question is, is there a more sane way to store this information, while
> still being able to find all the IP ranges that have the given IP in them?
> I've been only dealing with Cassandra for a week or two, so I don't know
> about the inner details of what can be done, but I do have programming
> experience and am not afraid to get my hands dirty, in case it can be solved
> by writing some extension to Cassandra.
> Looking forward to any suggestions.