val conf = new SparkConf().setAppName("MyApp").setMaster("local")
val sc = new SparkContext(conf)
val sqlcontext = new org.apache.spark.sql.SQLContext(sc)
sqlcontext.setConf("url", "mysql://localhost:3306/myDB?user=us&password=pw")

val action = sqlcontext.jdbc(jdbcUrl, "action").registerTempTable("action")
val session = sqlcontext.jdbc(jdbcUrl, "session").registerTempTable("session")
sqlcontext.cacheTable("action")
sqlcontext.cacheTable("session")

val data = sqlcontext.sql('SELECT * FROM action INNER JOIN session ON action.session_id = session.session_id")