Spark scala cassandra -


please see below code , let me know doing wrong?

using:

dse version - 5.1.0

connected test cluster @ 172.31.16.45:9042. [cqlsh 5.0.1 | cassandra 3.10.0.1652 | dse 5.1.0 | cql spec 3.4.4 | native protocol v4] use help.

thanks

cassandra table : cqlsh:tdata> select * map;   sno | name -----+------    1 |  1    2 |  2

-------------------------------------------

scala> :showschema tdata ======================================== keyspace: tdata ======================================== table: map ---------------------------------------- - sno : int (partition key column) - name : string

scala> val rdd = sc.cassandratable("tdata", "map")

scala> rdd.foreach(println)

i not getting here? not error.

you have hit common spark issue. println code being executed on remote executor jvms. means printout stdout of executor jvm process. if want bring data driver jvm before printing need collect call.

rdd  .collect //change rdd local collection  .foreach(println)

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