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! Apache Solr based search engine e-commerce
! .
!
! →
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! map-reduce ! 3
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Whole program comparison
Whole program comparison
Transformations
def filter(f: T => Boolean): RDD[T] def map[U: ClassTag](f: T => U): RDD[U] def foreachPartition(f: Iterator[T] => Unit) def zipWithIndex(): RDD[(T, Long)]
def join[W](other: RDD[(K, W)]): RDD[(K, (V, W))] def reduceByKey(func: (V,V) => V,numPartitions: Int):RDD[(K, V)]
In one partition(narrow)
Hadoop
Spark
Scala val file = spark.textFile("hdfs://...") val counts = file.flatMap(line => line.split(" ")) .map(word => (word, 1)) .reduceByKey(_ + _) counts.saveAsTextFile("hdfs://...")
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SQL
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! Classification and regression – linear support vector machine (SVM) – logistic regression – linear least squares, Lasso, and ridge regression – decision tree – naive Bayes ! Collaborative filtering
– alternating least squares (ALS)
– stochastic gradient descent – limited-memory BFGS (L-BFGS)
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Batch   Interac+ve   Streaming  
…
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API
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