On 4 February 2012 06:21, Yiming Sun <yiming.sun@gmail.com> wrote:
I cannot have one composite column name with 3 components while another with 4 components?
 Just put 4 components and left last empty (if it is same type)?!

Another question I have is how flexible composite columns actually are.  If my data model has a CF containing US zip codes with the following composite columns:

{OH:Spring Field} : 45503
{OH:Columbus} : 43085
{FL:Spring Field} : 32401
{FL:Key West}  : 33040

I know I can ask cassandra to "give me the zip codes of all cities in OH".  But can I ask it to "give me the zip codes of all cities named Spring Field" using this model?  Thanks.
No. You set first composite component at first.

I'd use a dynamic CF:
row key = state abbreviation 
column name = city name
column value = zip code (or a complex object, one of whose properties is zip code)

you can iterate over the columns in a single row to get a state's city names and their zip code and you can do a get_range_slices on all keys for the columns starting and ending on the city name to find out the zip codes for a cities with the given name.

I think

- Chris