convert RDD[CassandraRow] to RDD[String]

Question

is it possible to convert RDD[CassandraRow] to RDD[String] ? if so , is there any disadvantage of working against the converted RDD ?

Answer 1

You can use sqlContext to read data from Cassandra table, it returns an DataFrame, and when you read text file using sparkContext it returns RDD and then you can convert that to DataFrame.

If your text files are CSV, Spark 2.0 Supports csv data source, it returns an DataFrame by deafult. Please see this.. https://spark.apache.org/releases/spark-release-2-0-0.html#new-features and https://github.com/databricks/spark-csv/issues/

Update:

https://databricks.com/blog/2015/04/13/deep-dive-into-spark-sqls-catalyst-optimizer.html