I think you are correct, David. What Bill is asking for specifically is not in the API.
Bill, if this is a performance concern (i.e., your column values are/could be vastly larger than your column names, and you need to query the namespace before loading the values), then you might consider keeping a separate column family which just contains the column names and timestamps with empty values. On Sun, May 16, 2010 at 4:37 AM, David Boxenhorn <da...@lookin2.com> wrote: > Bill, I am a new user of Cassandra, so I've been following this discussion > with interest. I think the answer is "no", except for the brute force method > of looping through all your data. It's like asking for a list of all the > files on your C: drive. The term "column" is very misleading, since > "columns" are really leaves of a tree structure, not columns of a tabular > structure. > > Anybody want to tell me I'm wrong? > > BTW, Bill, I think we've corresponded before, here: > http://www.dehora.net/journal/2004/04/whats_in_a_name.html > > On Fri, May 14, 2010 at 2:23 AM, Bill de hOra <b...@dehora.net> wrote: >> >> A SlicePredicate/SliceRange can't exclude column values afaik. >> >> Bill >> >> Jonathan Shook wrote: >>> >>> get_slice >>> >>> see: http://wiki.apache.org/cassandra/API under get_slice and >>> SlicePredicate >>> >>> On Thu, May 13, 2010 at 9:45 AM, Bill de hOra <b...@dehora.net> wrote: >>>> >>>> get_count returns the number of columns, not the names of those columns? >>>> I >>>> should have been specific, by "list the columns", I meant "list the >>>> column >>>> names". >>>> >>>> Bill >>>> >>>> Gary Dusbabek wrote: >>>>> >>>>> We have get_count at the thrift level. You supply a predicate and it >>>>> returns the number of columns that match. There is also >>>>> multi_get_count, which is the same operation against multiple keys. >>>>> >>>>> Gary. >>>>> >>>>> >>>>> On Thu, May 13, 2010 at 04:18, Bill de hOra <b...@dehora.net> wrote: >>>>>> >>>>>> Admin question - is there a way to list the columns for a particular >>>>>> key? >>>>>> >>>>>> Bill >>>>>> >>>> >> > >
