Skip to content

Instantly share code, notes, and snippets.

@chaityacshah
Forked from tmcgrath/Spark aggregateByKey
Created October 23, 2019 18:58
Show Gist options
  • Star 0 You must be signed in to star a gist
  • Fork 0 You must be signed in to fork a gist
  • Save chaityacshah/17ca14b4de387db2e9d6357084bde8b7 to your computer and use it in GitHub Desktop.
Save chaityacshah/17ca14b4de387db2e9d6357084bde8b7 to your computer and use it in GitHub Desktop.
Spark aggregateByKey example
Welcome to
____ __
/ __/__ ___ _____/ /__
_\ \/ _ \/ _ `/ __/ '_/
/___/ .__/\_,_/_/ /_/\_\ version 1.1.0
/_/
Using Scala version 2.10.4 (Java HotSpot(TM) 64-Bit Server VM, Java 1.6.0_65)
Type in expressions to have them evaluated.
Type :help for more information.
2014-12-02 08:40:25.812 java[2479:1607] Unable to load realm mapping info from SCDynamicStore
14/12/02 08:40:25 WARN NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Spark context available as sc.
scala> val babyNamesCSV = sc.parallelize(List(("David", 6), ("Abby", 4), ("David", 5), ("Abby", 5)))
babyNamesCSV: org.apache.spark.rdd.RDD[(String, Int)] = ParallelCollectionRDD[0] at parallelize at <console>:12
scala> babyNamesCSV.reduceByKey((n,c) => n + c).collect
res0: Array[(String, Int)] = Array((Abby,9), (David,11))
scala> babyNamesCSV.aggregateByKey(0)((k,v) => v.toInt+k, (v,k) => k+v).collect
res1: Array[(String, Int)] = Array((Abby,9), (David,11))
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment