15-Day PySpark for Data Engineering Master Guide-v2
Apache Spark Fundamentals Why Spark exists & core concepts š„ What is Spark A distributed data processing engine for massive datasets, supporting batch, streaming, SQL, ML & Graph processing. in-memory š¢→š Why Spark Replaces slow MapReduce with in-memory computation, complex ETL pipelines, and real-time distributed analytics. speed šø️ Lazy Evaluation Spark does NOT execute immediately. Execution only triggers on Actions — this allows DAG optimization and reduced cost. ⭐ critical š DAG Directed Acyclic Graph — Spark's execution plan. Visualizes Stages, Tasks, Lineage, and the optimization flow. internals š️ Spark Architecture Driver → Cluster Manager → Executors DRIVER SparkSession DAG Scheduler Task Dispatcher submit CLUSTER MANAGER YARN Kubernetes Standalone Resources EXECUTOR 1 Task · Task · Task Cache / Memory Partitions EXECUTOR 2 Task · Task · Task Cache / Memory Partitions STORAGE HDFS S3 / ADLS Delta Lake Parquet controls allocates executes persists JOB → STAG...