On Sat, Jun 19, 2010 at 9:30 AM, Christian van der Leeden <christian.vanderlee...@googlemail.com> wrote: > Hi Thomas, > > did you look at cassandra gem from twitter (fauna/cassandra) on github? > They also use the thrift_client and already have the basic cassandra API > accessible. > > I'm also using ruby with cassandra and still need to find a slick way to do > the inserts > and when to update the indexes.
Have you looked at CassandraObject for that? http://github.com/nzkoz/cassandra_object -ryan > > If I understood correctly you want to look up a user by name. And you want to > have > the name as row keys where you would find the UID with which you could look > up your user? > > From my understanding I would put the index into one row, name it e.g. > "user_by_name", > and insert columns where the column name is the user name and the value of > the column > would be the UUID of the user. Cassandra creates the index on the column > names. You can > efficiently insert new values into this row. > > What do you want to do with the users partitioned by date? Sorted by creation > date? Login date? > > For the cascading deletes: a database would have to remove a record from its > index, too. > In Cassandra you would have to do it yourself.. > > Christian > > On Jun 19, 2010, at 3:27 AM, Thomas Heller wrote: > >> Howdy! >> >> So, last week I finally got around to playing with Cassandra. After a >> while I understood the basics. To test this assumption I started >> working on my own Client implementation since "Learning-by-doing" is >> what I do and existing Ruby Clients (which are awesome) already >> abstracted too much for me to really grasp what was going on. Java is >> not really my thing (anymore) so I began with the Thrift API and Ruby. >> >> Anyways back to Topic. >> >> This library is now is available at: >> http://github.com/thheller/greek_architect >> >> Since I have virtually no experience with Cassandra (but plenty with >> SQL) I started with the first use-case which I have programmed a bunch >> of times before. User Management. I build websites which are used by >> other people, so I need to store them somewhere. >> >> Step #1: Creating Users and persisting them in Cassandra >> >> Example here: >> http://github.com/thheller/greek_architect/blob/master/spec/examples/user_create_spec.rb >> >> I hope my rspec-style documentation doesnt confuse too many people >> since I already have a gazillion questions for this simple, but also >> VERY common use-case. Since a question is best asked with a concrete >> example to refer to, here goes my first one: >> >> Would any of you veterans build what I built the way I did? (refering >> to the cassandra design, not the ruby client) >> >> I insert Users with UUID keys into one ColumnFamily. I then index them >> by creating a row in another ColumnFamily using the Name as Key and >> then adding one column holding a reference to the User UUID. I also >> insert a reference into another ColumnFamily holding a List of Users >> partitioned by Date. >> >> I'm really unsure about the index design, since they dont get updated >> when a User row is removed. I could hook into the remove call (like I >> did into mutations) and cascade the deletes where needed, but 10+ >> years of SQL always want to tell me I'm crazy for doing this stuff! >> >> I'd really appreciate some feedback. >> >> Cheers, >> Thomas > >
