In ancient versions of pycassa (that is, before 1.3), the simplest idiom to get just a list of all keys of a column family was
for key, _ in cf.get_range(columns=()):
Since 1.3 the get_range() method accepts a filter_empty keyword, True by default, that just caused half-an-hour of headscratching, because the above snippet clearly does nothing...
Not a serious issue, once I understood what's going on... but I wonder if giving an empty columns should take precedence over the filter_empty.
Alternatively, should ColumnFamily grow a more specialized get_keys() method?
Actually, those both sound like good ideas to me. I think we should do both.