Done! Thank you Pedro Gomes
On May 22, 2010, at 2:07 AM, Jonathan Ellis wrote: > Thanks! > > You should probably add it to http://wiki.apache.org/cassandra/ClientOptions. > > On Fri, May 21, 2010 at 12:22 PM, Pedro Gomes > <pedrogo...@lsd.di.uminho.pt> wrote: >> Hi all >> In the following weeks I have developed a plugin to the java persistence >> platform Datanucleus, similar to the one presented by Google for App Engine >> and a Hbase already present in the platform . >> Datanucleus: http://www.datanucleus.org/project/download.html >> For now it allows the persistence of simples fields and one-one, one-many, >> and many-many relations, supporting collections and maps, arrays are next >> through the Java Data Objects (JDO) API. >> The platform allows a query language JDOQL, but I didn't add the support for >> it. >> You can access the project under : >> http://github.com/PedroGomes/datanucleus-cassandra >> Any feedback or doubts are welcome. >> I still have, though, some doubts on the implementation. To store many-many, >> and one to many relations in Cassandra, i.e., one collection/map of pointers >> to other objects I see two options: >> -The column, in the Column family class, correspondent to the relation >> contains a collection or map that codes the relation, i.e. it stores the ids >> to the objects,. This can be dangerous if the collection/map grows large. >> -You have a column family that codes relations, one simple Column family per >> relation, or a Super Column family that codes all relations . This approach >> however, makes each fetch from the collection takes 3 read steps, but each >> object id is stored separately. >> Other option that I'm thinking is a hybrid solution where the user chooses >> the pretended option. >> If someone can give some advice on this, I would be thankful. >> Grateful >> Pedro Gomes >> >> >> >> >> >> > > > > -- > Jonathan Ellis > Project Chair, Apache Cassandra > co-founder of Riptano, the source for professional Cassandra support > http://riptano.com
