Overview
This lecture provides a detailed introduction to AWS Glue ETL, explains its key features, and demonstrates how to create and run a basic ETL job using the visual interface.
Introduction to AWS Glue ETL
- ETL stands for Extract, Transform, and Load, crucial in data engineering for moving and processing data.
- AWS Glue ETL is a fully managed service by AWS for performing ETL operations.
- Glue ETL eliminates the need for managing servers and infrastructure.
Features of AWS Glue ETL
- Fully managed: AWS handles all hardware, scaling, and software updates.
- Serverless: No need to provision or manage servers.
- Integrated with Apache Spark for scalable big data processing.
- Multiple development options: visual (drag-and-drop), code-based (PySpark scripts), and interactive notebooks.
- Built-in scheduling, orchestration, and monitoring of ETL workflows.
- Easy connectivity with various AWS and external data sources (e.g., S3, Redshift, RDS).
Creating a Visual ETL Job in AWS Glue
- Example use case: Transform customer data from one S3 folder to another.
- Requirements: Input data in S3 and an IAM role with S3, Glue, and CloudWatch permissions.
- Visual ETL allows users to set source, apply transformations, and define targets via a UI.
- Source setup: Select S3 location or Glue Data Catalog table; preview data if needed.
- Transformation example: Dropping a specific field (e.g., last name) from the CSV.
- Target setup: Write transformed data to another S3 path in Parquet format with compression.
Running and Monitoring the Job
- Glue automatically generates an ETL script based on UI selections.
- Job execution is managed by AWS without manual server setup.
- Processing resources can be adjusted (e.g., DPU, worker type).
- Job status and logs can be monitored within the AWS Glue console.
Key Terms & Definitions
- ETL — Extract, Transform, Load: process of moving and transforming data between systems.
- Fully managed — AWS handles infrastructure, scaling, and software for you.
- Serverless — No need to maintain or deploy servers.
- Apache Spark — Distributed processing framework included in Glue for big data tasks.
- Dynamic Frame — Glue’s abstraction for handling datasets, especially for semi-structured data.
- IAM Role — AWS Identity and Access Management role that grants permissions for Glue jobs.
Action Items / Next Steps
- Create an IAM role with S3, Glue, and CloudWatch permissions for your ETL jobs.
- Prepare your sample data in S3 and optionally set up a Glue Data Catalog table.
- Practice creating a Glue ETL job using the visual interface as demonstrated.
- Read output files in the target location to verify the applied transformations.
- Prepare for upcoming lessons on developing ETL jobs using PySpark scripts.