Excerpts from Edward Leafe's message of 2016-05-03 08:20:36 -0700: > On May 3, 2016, at 6:45 AM, Miles Gould <mgo...@redhat.com> wrote: > > >> This DB could be an RDBMS or Cassandra, depending on the deployer's > >> preferences > > AFAICT this would mean introducing and maintaining a layer that abstracts > > over RDBMSes and Cassandra. That's a big abstraction, over two quite > > different systems, and it would be hard to write code that performs well in > > both cases. If performance in this layer is critical, then pick whichever > > DB architecture handles the expected query load better and use that. > > Agreed - you simply can’t structure the data the same way. When I read > criticisms of Cassandra that include “you can’t do joins” or “you can’t > aggregate”, it highlights this fact: you have to think about (and store) your > data completely differently than you would in an RDBMS. You cannot simply > abstract out the differences. >
Right, once one accepts that fact, Cassandra looks a lot less like a revolutionary database, and a lot more like a sharding toolkit. __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
