CCA175 Exam Dumps : CCA Spark and Hadoop Developer Exam

Solution :

b.foidByKey("")(_ + J.collect

foldByKey [Pair]

Very similar to fold, but performs the folding separately for each key of the RDD. This function is only available if the RDD consists of two-component tuples

Listing Variants

def foldByKey(zeroValue: V)(func: (V, V) => V): RDD[(K, V}]

def foldByKey(zeroValue: V, numPartitions: lnt)(func: (V, V) => V): RDD[(K, V)]

def foldByKey(zeroValue: V, partitioner: Partitioner)(func: (V, V) => V): RDD[(K, V}]

Solution :

Step 1 : create employee.json tile locally.

vi employee.json (press insert) past the content.

Step 2 : Upload this tile to hdfs, default location hadoop fs -put employee.json

Step 3 : Write spark script

#lmport SQLContext

from pyspark import SQLContext

#Create instance of SQLContext sqIContext = SQLContext(sc)

#Load json file

employee = sqlContext.jsonFile("employee.json")

#Register RDD as a temp table employee.registerTempTablef'EmployeeTab"}

#Select data from Employee table

employeelnfo = sqlContext.sql("select * from EmployeeTab"}

#lterate data and print

for row in employeelnfo.collect():

print(row)

Step 4 : Write dataas a Text file employeelnfo.toJSON().saveAsTextFile("employeeJson1")

Step 5: Check whether data has been created or not hadoop fs -cat employeeJsonl/part"

Solution :

Step 1 : Create an RDD out of this list

val rdd = sc.parallelize(List( ("Deeapak" , "male", 4000}, ("Deepak" , "male", 2000), ("Deepika" , "female", 2000),("Deepak" , "female", 2000), ("Deepak" , "male", 1000} , ("Neeta" , "female", 2000}}}

Step 2 : Convert this RDD in pair RDD

val byKey = rdd.map({case (name,sex,cost) => (name,sex)->cost})

Step 3 : Now group by Key

val byKeyGrouped = byKey.groupByKey

Step 4 : Nowsum the cost for each group

val result = byKeyGrouped.map{case ((id1,id2),values) => (id1,id2,values.sum)}

Step 5 : Save the results result.repartition(1).saveAsTextFile("spark12/result.txt")