Returns a view of a Cassandra table as CassandraRDD.
Returns a view of a Cassandra table as CassandraRDD.
This method is made available on SparkContext by importing com.datastax.spark.connector._
Depending on the type parameter passed to cassandraTable, every row is converted to one of the following:
Example:
CREATE KEYSPACE test WITH replication = {'class': 'SimpleStrategy', 'replication_factor': 1 };
CREATE TABLE test.words (word text PRIMARY KEY, count int);
INSERT INTO test.words (word, count) VALUES ('foo', 20);
INSERT INTO test.words (word, count) VALUES ('bar', 20);
...// Obtaining RDD of CassandraRow objects: val rdd1 = sc.cassandraTable("test", "words") rdd1.first.getString("word") // foo rdd1.first.getInt("count") // 20 // Obtaining RDD of tuples: val rdd2 = sc.cassandraTable[(String, Int)]("test", "words").select("word", "count") rdd2.first._1 // foo rdd2.first._2 // 20 // Obtaining RDD of user defined objects: case class WordCount(word: String, count: Int) val rdd3 = sc.cassandraTable[WordCount]("test", "words") rdd3.first.word // foo rdd3.first.count // 20
Provides Cassandra-specific methods on
SparkContext