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44 lines
2.3 KiB
Markdown
44 lines
2.3 KiB
Markdown
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---
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layout: doc_page
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---
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Druid vs Spark
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==============
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Druid and Spark are complementary solutions as Druid can be used to accelerate OLAP queries in Spark.
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Spark is a general cluster computing framework initially designed around the concept of Resilient Distributed Datasets (RDDs).
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RDDs enable data reuse by persisting intermediate results
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in memory and enable Spark to provide fast computations for iterative algorithms.
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This is especially beneficial for certain work flows such as machine
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learning, where the same operation may be applied over and over
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again until some result is converged upon. The generality of Spark makes it very suitable as an engine to process (clean or transform) data.
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Although Spark provides the ability to query data through Spark SQL, much like Hadoop, the query latencies are not specifically targeted to be interactive (sub-second).
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Druid's focus is on extremely low latency queries, and is ideal for powering applications used by thousands of users, and where each query must
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return fast enough such that users can interactively explore through data. Druid fully indexes all data, and can act as a middle layer between Spark and your application.
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One typical setup seen in production is to process data in Spark, and load the processed data into Druid for faster access.
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For more information about using Druid and Spark together, including benchmarks of the two systems, please see:
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<https://www.linkedin.com/pulse/combining-druid-spark-interactive-flexible-analytics-scale-butani>
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