I don't understand. By the way, the `joinWithCassandraTable` does improve my query time from 40 mins to 3 mins.
2015-07-15 13:19 GMT+08:00 ÐΞ€ρ@Ҝ (๏̯͡๏) <deepuj...@gmail.com>: > I have explored spark joins for last few months (you can search my posts) > and its frustrating useless. > > On Tue, Jul 14, 2015 at 9:35 PM, Wush Wu <wush...@gmail.com> wrote: >> >> Dear all, >> >> I have found a post discussing the same thing: >> >> https://groups.google.com/a/lists.datastax.com/forum/#!searchin/spark-connector-user/join/spark-connector-user/q3GotS-n0Wk/g-LPTteCEg0J >> >> The solution is using "joinWithCassandraTable" and the documentation >> is here: >> https://github.com/datastax/spark-cassandra-connector/blob/v1.3.0-M2/doc/2_loading.md >> >> Wush >> >> 2015-07-15 12:15 GMT+08:00 Wush Wu <wush...@gmail.com>: >> > Dear all, >> > >> > I am trying to join two RDDs, named rdd1 and rdd2. >> > >> > rdd1 is loaded from a textfile with about 33000 records. >> > >> > rdd2 is loaded from a table in cassandra which has about 3 billions >> > records. >> > >> > I tried the following code: >> > >> > ```scala >> > >> > val rdd1 : (String, XXX) = sc.textFile(...).map(...) >> > import org.apache.spark.sql.cassandra.CassandraSQLContext >> > cc.setKeyspace("xxx") >> > val rdd2 : (String, String) = cc.sql("SELECT x, y FROM xxx").map(r => >> > ...) >> > >> > val result = rdd1.leftOuterJoin(rdd2) >> > result.take(20) >> > >> > ``` >> > >> > However, the log shows that the spark loaded 3 billions records from >> > cassandra and only 33000 records left at the end. >> > >> > Is there a way to query the cassandra based on the key in rdd1? >> > >> > Here is some information of our system: >> > >> > - The spark version is 1.3.1 >> > - The cassandra version is 2.0.14 >> > - The key of joining is the primary key of the cassandra table. >> > >> > Best, >> > Wush >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: user-unsubscr...@spark.apache.org >> For additional commands, e-mail: user-h...@spark.apache.org >> > > > > -- > Deepak > --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@spark.apache.org For additional commands, e-mail: user-h...@spark.apache.org