Spark 2.3.1的编程指导内容如下：
Quick Start
Spark2.0前Spark主要编程接口是RDDs，2.0之后，RDDs接口被Dataset接口取代，Dataset和RDDs一样是强类型，但是底层做了大量优化。RDDs接口仍然可用，但是强烈推荐转换使用Dataset，性能比RDDs好
Spark Shell
基础
bin/spark-shell
Dataset操作
transformations
actions
缓存Caching
cache()是persist(StorageLevel.MEMORY_ONLY)的简写
persist(StorageLevel.MEMORY_ONLY)等
自包含应用
A self-contained application consists of a single, installable bundle that contains your application and a copy of the JRE needed to run the application. When the application is installed, it behaves the in the same way as any native application.