As organizations increasingly rely on data to drive business decisions, choosing the right data warehouse is critical. With numerous options available in the market, Snowflake, Amazon Redshift, and Google BigQuery are three of the most popular cloud-based data warehousing solutions. Each platform offers unique strengths, pricing models, and capabilities. In this blog, we’ll compare these […]
Read MoreIn today’s data-driven world, organizations are constantly looking for faster, scalable, and cost-effective solutions to handle large volumes of data. Snowflake is one such cloud-based data warehousing platform that has revolutionized how businesses manage, analyze, and share their data. In this blog, we’ll dive deep into what Snowflake is, its architecture, and the features that […]
Read MoreMust-Know Delta Lake Commands for Data Engineers in 2025 (with Examples) As organizations scale, traditional data lakes often fail due to lack of consistency, governance, and reliability. Delta Lake solves these challenges by combining the scalability of data lakes with the reliability of data warehouses. In this blog, we’ll cover the most essential Delta Lake […]
Read MoreRunning a Spark Batch Job on Google Cloud Dataproc As Data Engineers, one of the most powerful capabilities we often use is running batch Spark jobs on cloud clusters. Google Cloud Dataproc makes this seamless by letting us submit jobs directly to a managed Spark cluster. Here’s how I recently submitted a batch Spark job […]
Read MoreProblem StatementTruecaller deals with millions of user settings change events daily.Each event looks like this: id (long)name (string)value (string)timestamp (long)The goal: Group events by id. Convert (name, value) pairs into a Map. Always pick the value for each key that has the latest timestamp. Output a partitioned table for faster downstream queries. Example: id name […]
Read MoreIntroductionRetail today is not just about selling products – it’s about instant insights. Customers expect personalized offers, faster checkouts, and always-available inventory. For that, retailers need real-time data processing. In this tutorial, we’ll build a real-time data streaming pipeline for a retail company using Google Cloud Pub/Sub. Use CaseA retail chain with 500+ stores wants […]
Read MoreCatalyst Optimizer in Spark 3.0: Types, Use Cases, and Real-World CommandsIf you’re working with big data, speed matters. Spark 3.0 introduced major internal improvements—none more powerful than the Catalyst Optimizer and Adaptive Query Execution (AQE). 🧠 What is Catalyst Optimizer?It’s Spark’s rule-based and cost-based optimizer. Every time you write PySpark code, it: Converts it to […]
Read MorePySpark vs Pandas – When to Use What for Big Data “Should I use Pandas or PySpark for my data processing?” Let’s break this down across key dimensions with real examples: 1️⃣ Performance & ScalabilityFeature Pandas PySparkExecution Single-threaded Distributed (multi-node)In-memory limit Limited to RAM Designed for TBs+File handling Local files only HDFS, S3, GCS, JDBC, […]
Read More“If you have 100GB of data, how do you process it efficiently in PySpark?” It’s a classic interview question — but also a real challenge every data engineer faces when working with big data in production. Let’s break down the best practices step by step, using practical commands you can reuse in your projects. ✅ […]
Read MoreSource: Real-time CSV files with stock prices Target: JSON format files consumable by Data Analysts Goal: Automate the transformation and cataloging for query-ready analytics 🛠️ Step-by-Step Pipeline with AWS Services🔹 1. CSV Files Drop into S3Incoming files: stock data like stock_data_2025-06-16.csv S3 Source Bucket: s3://reedx-stock-raw/ These files were pushed by upstream providers or batched ingestion […]
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