摘要:
语法是: combineByKey[C]( createCombiner: V => C, mergeValue: (C, V) => C, mergeCombiners: (C, C) => C ) 标记一下:(因为有很多同样的字母,方便说明我就按照字母+数字标记一下) 语法说明:(不复制网上的, 阅读全文
摘要:
spark 创建分区 val scores = Array(("Fred", 88), ("Fred", 95), ("Fred", 91), ("Wilma", 93), ("Wilma", 95), ("Wilma", 98)) val input = sc.parallelize(scores 阅读全文