1.数据的读取
object TestRead {
def main(args: Array[String]): Unit = {
val conf = new SparkConf().setAppName("TestDataFrame2").setMaster("local")
val sc = new SparkContext(conf)
val sqlContext = new SQLContext(sc)
//方式一
val df1 = sq
导读
:: DeveloperApi ::
Holds all the runtime environment objects for a running Spark instance (either master or worker),
保存一个运行中的Spark实例的所有运行时环境对象(master或worker),
including the serializer, RpcEnv, block manager, map output tracker, etc. Currentl