创作都市模板

Spark RDD的关联操作 join 关联 Spark默认的join是inner join操作,即两边都有的键 初始化 val a1=sc.parallelize(Array(("K1","V1"),("K2","V2"),("K3","V3"))) val a2=sc.parallelize(Array(("K1","V2"),("K3","B3"),("K4","V4"))) join a...

2.4.4 RDD Programming Guide RDD编程指导 Overview At a high level, every Spark application consists of a driver program that runs the user’s main function and executes various parallel operations on a clus...