Apache Spark aggregateByKey Example

In this Spark aggregateByKey example post, we will discover how aggregationByKey could be a better alternative of groupByKey transformation when aggregation operation is involved. The most common problem while working with key-value pairs is grouping of values and aggregating them with respect to a common key. And Spark aggregateByKey transformation decently addresses this problem in a very intuitive way.

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Apache Spark groupByKey Example

Apache Spark groupByKey example is quite similar as reduceByKey. It is again a transformation operation and also a wider operation because it demands data shuffle. Looking at spark groupByKey function it takes key-value pair (K,V) as an input produces RDD with key and list of values. Let’s try to understand the function in detail. At the end of this post we’ll also compare it with reduceByKey with respect to optimization technique.

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Apache Spark RDD Operations: Transformation and Action

We have already discussed about Spark RDD in my post Apache Spark RDD : The Bazics. In this post we’ll learn about Spark RDD Operations in detail. As we know Spark RDD is distributed collection of data and it supports two kind of operations on it Transformations and Actions. Continue reading “Apache Spark RDD Operations: Transformation and Action”