that's another "pipeline" step to add whereas when using persist is just relevant during the lifetime of your jobs and not in HDFS but in the local disk of your executors.
On Wed, Aug 17, 2016 5:56 PM, neil90 [email protected] wrote: >From the spark documentation(http://spark.apache.org/docs/latest/programming-guide.html#rdd-persistence) yes you can use persist on a dataframe instead of cache. All cache is, is a shorthand for the default persist storage level "MEMORY_ONLY". If you want to persist the dataframe to disk you should do dataframe.persist(StorageLevel.DISK_ONLY). IMO If reads are expensive against the DB and your afraid of failure why not just save the data as a parquet on your cluster in hive and read from there? -- View this message in context: http://apache-spark-user-list.1001560.n3.nabble.com/Spark-DF-CacheTable-method-Will-it-save-data-to-disk-tp27533p27551.html Sent from the Apache Spark User List mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe e-mail: [email protected] Olivier Girardot | AssociƩ [email protected] +33 6 24 09 17 94
