Also note that the BMT example in contrib is an example of a hadoop process writing to Cassandra.
On Tue, May 18, 2010 at 12:52 PM, Stu Hood <[email protected]> wrote: > A Cassandra OutputFormat was recently contributed, but I haven't had a > chance to review it. Any feedback you can give would be awesome: > https://issues.apache.org/jira/browse/CASSANDRA-1101 > > Thanks, > Stu > > -----Original Message----- > From: "Jeff Zhang" <[email protected]> > Sent: Tuesday, May 18, 2010 4:39am > To: [email protected] > Subject: Re: mapreduce from cassandra to cassandra > > BTW, maybe we should create an issue on jira for this problem if the > Cassandra committee think it is necessary. > > > > On Tue, May 18, 2010 at 5:30 PM, Jeff Zhang <[email protected]> wrote: > > reuse is not possible, but I think it won't hard for cassandra to > > implement a ColumnFamilyOutputFormat. In my opinion, the > > ColumnFamilyOutputFormat should be easier to implement than > > ColumnFamilyInputFormat, because you don't need to think about split > > in the implementation of OutputFormat. > > > > > > > > > > > > On Tue, May 18, 2010 at 5:22 PM, Ran Tavory <[email protected]> wrote: > >> hbase - yes. But is that reusable for cassandra? > >> > >> On Tue, May 18, 2010 at 12:17 PM, Jeff Zhang <[email protected]> wrote: > >>> > >>> I believe it is possible to write result back to cassandra. If I > >>> remember correctly, HBase has both InputFormat and OutputFormat for > >>> hadoop. > >>> > >>> > >>> > >>> > >>> On Tue, May 18, 2010 at 5:08 PM, Ran Tavory <[email protected]> wrote: > >>> > In the wordcount example the process reads from cassandra and the > result > >>> > is > >>> > written to a local file at /tmp/word_count* > >>> > Is it possible to read from cassandra and write the result back to > >>> > cassandra > >>> > to a specified cf/row/column? > >>> > I see that there exists a ColumnFamilyInputFormat but not > >>> > ColumnFamilyOutputFormat or something like that > >>> > > >>> > (in > http://svn.apache.org/repos/asf/cassandra/trunk/src/java/org/apache/cassandra/hadoop/ > ) > >>> > My knowledge about hadoop and mr is pretty basic so maybe I'm missing > >>> > something simple, lmk, thanks! > >>> > >>> > >>> > >>> -- > >>> Best Regards > >>> > >>> Jeff Zhang > >> > >> > > > > > > > > -- > > Best Regards > > > > Jeff Zhang > > > > > > -- > Best Regards > > Jeff Zhang > > >
