Apache Spark

Originally published on Sync Computing Databricks’ DLT offering showcases a substantial improvement in the data engineer lifecycle and workflow. By offering a pre-baked, and opinionated pipeline construction ecosystem, Databricks has finally started offering a holistic end-to-end data engineering experience from inside of its own product, which provides superior solutions for raw data workflow, live batching and a host of other benefits detailed below. Since its release in 2022, Databricks’ Delta Live Tables have quickly become a go-to end-to-end resource for data engineers looking to build opinionated ETL pipelines for streaming data and big data. The pipeline management framework is considered one of the most valuable offerings on the databricks platform, and is used by over 1,000 companies including Shell and H&R block. ...

Originally published on Efficiently (Substack) We’ve spoken a lot about on-disk and distributed storage, as well as blocks. All of this theory is great, let’s talk about this in practice. In this post, I’m going to: Read a CSV dataset into Spark Write the dataset into 5 Parquet files (treating each file as a block) Introspect metadata existing on the files Run queries demonstrating predicate pushdown power Hands-On: Setup The tutorial uses an airports dataset. Download it via: ...

Originally published on Efficiently (Substack) A few years ago, I gave a talk at Spark Summit 2020 about File Formats covering Avro, ORC, and Parquet. I received numerous questions about that topic, responding point-to-point, leaving the knowledge confined to those forums alone. That isn’t helpful for most people. This post aims to fix that. In this series, I’ll outline the primitives of this topic and then explore the hands-on details. Problem In the efficiency space, minimizing “work” is key. Whether work requires compute, network, or storage, “the goal of efficient data usage is to get the most accurate answer in the fastest and cheapest way possible.” ...

In a world where compute is paramount, it is all too easy to overlook the importance of storage and IO in the performance and optimization of Spark jobs. In reality, the choice of file format has drastic implications to everything from the ongoing stability to compute cost of compute jobs. These file formats also employ a number of optimization techniques to minimize data exchange, permit predicate pushdown, and prune unnecessary partitions. This session aims to introduce and concisely explain the key concepts behind some of the most widely used file formats in the Spark ecosystem – namely Parquet, ORC, and Avro. We’ll discuss the history of the advent of these file formats from their origins in the Hadoop / Hive ecosystems to their functionality and use today. We’ll then deep dive into the core data structures that back these formats, covering specifics around the row groups of Parquet (including the recently deprecated summary metadata files), stripes and footers of ORC, and the schema evolution capabilities of Avro. We’ll continue to describe the specific SparkConf / SQLConf settings that developers can use to tune the settings behind these file formats. We’ll conclude with specific industry examples of the impact of the file on the performance of the job or the stability of a job (with examples around incorrect partition pruning introduced by a Parquet bug), and look forward to emerging technologies (Apache Arrow). ...