is it bad to have lots of column families?

in a traditional database it's not a good a idea to have hundreds of tables but is it also bad to have hundreds of column families in cassandra? thank you.

simplest example of a query by date range

I want to store an ID and a date and I want to retrieve all entries from dateA up to dateB, what exactly do I need to be able to perform: select from my_column_family where date >= dateA and date < dateB; @so: http://stackoverflow.com/q/8638646/226201