Accessing Cassandra from Spark
DataStax Enterprise integrates Spark with Cassandra. Cassandra tables are fully usable from Spark.
DataStax Enterprise integrates Spark with Cassandra. Cassandra tables are fully usable from Spark.
Accessing Cassandra from a Spark application
To access Cassandra from a Spark application, follow instructions in the Spark example Portfolio Manager demo using Spark.Accessing Cassandra from the Spark shell
DataStax Enterprise uses the Spark Cassandra Connector to provide Cassandra integration for Spark. By running the Spark shell in DataStax Enterprise, you have access to enriched Spark context objects for accessing Cassandra directly. See the Spark Cassandra Connector Java Doc on GitHub.
To access Cassandra from the Spark Shell, just run the dse spark
command
and follow instructions in subsequent sections.
$ dse spark
Welcome to
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Using Scala version 2.10.5 (OpenJDK 64-Bit Server VM, Java 1.8.0_91)
Type in expressions to have them evaluated.
Type :help for more information.
Creating SparkContext...
Created spark context..
Spark context available as sc.
Hive context available as sqlContext. Will be initialized on first use.
scala>
The Spark Shell creates two contexts by default: sc (an instance of org.apache.spark.SparkContext) and sqlContext (an instance of org.apache.spark.sql.hive.HiveContext).
val hc=sqlContext
Previous versions also created a
CassandraSqlContext instance named csc. Starting in
DSE 5.0, this is no longer the case. Use the sqlContext object
instead.