spark算子分类记忆

转换算子 27个

单Value类型：13

    map,mapPartitions,mapPartitionsWithIndex,flatMap,glom,groupBy,filter,sample,distinct,coalesce,repartition,sortBy,pipe

双Value类型：4

    intersection,union,subtract,zip,

Key-Value类型：10

    partittionBy,reduceByKey,groupByKey,aggregateByKey,foldByKey,combineByKey,sortByKey,join,leftOuterJoin,cogroup

行动算子 11种

reduce,collect,count,first,take,takeOrdered,aggregate,fold,countBykey,saveAsTextFile相关算子，foreach