On Wed, 3 Mar 2010 14:43:14 +0100 Alexandre Conrad <alexandre.con...@gmail.com> wrote:
AC> 2010/3/3 Ted Zlatanov <t...@lifelogs.com>: >> I don't understand the advantages of ColumnFamilies over a >> SuperColumnFamily with just one supercolumn. Why have the former if the >> latter is functionally equivalent? AC> As far as I understand, there's how I organize Cassandra entities: AC> http://paste.pocoo.org/show/185126/ AC> Is this somehow correct? This was your diagram (fixed-width font required): > KeySpace > | > +-- Row > | > +-- ColumnFamily > | > +-- Column > | > +-- SuperColumn > | > +-- Column That's incorrect. Here's a (shorter, correct) version: KeySpace->Row->ColumnFamily->Column[name, value] (a two-level map) KeySpace->Row->SuperColumnFamily->SuperColumn[name]->Column[name, value] (a three-level map) My point was that conceptually, the three-level map can express the two-level map. Ted
