Cassandra may not be the best fit for a billing system. I'm guessing the lack of transactions would be a problem if you want to update inventory levels.

If you want to get data from multiple column families you will need to make multiple calls, or de-normalise the data so you can get all the data you need from one column family for a single key. Such as storing the inventory data in the same column family as the product info. Perhaps using a Super Column Family with a super column for the ProductData, another for the Inventory etc. You could then read all the colums in the CF for one product and get all the data you want without doing a join.

In general do-normalise to remove the need for joins. Also be aware of the transaction guarantees you are giving up.

Hope that helps.
Aaron

On 20 Jul, 2010,at 04:03 PM, bujji <sivaits4u@gmail.com> wrote:

Hi all,

I am new to Cassandra...

I want to use to cassandra for a billing system.

As I saw in many places that Joins won't work in BigTable implementation but i feel i needed it for my App.

I am unable to get the data from multiple tables (columnFamilies) like products and inventory

As I am trying to do some joins implementation but fails....

Can I do it without joins ?

Can anybody give me some good model to use for my application or any standard example 
please help me folks,

Thanks ,
Bujji