Most Data Engineers learn PySpark before SQL. Airflow before Linux. Cloud before Python. Then wonder why they struggle. Don't build the roof before the foundation. Master these 3 first 👇 1️⃣ Linux File system • Permissions • SSH grep • find • Bash scripting Cron jobs • Log analysis • Process monitoring 2️⃣ SQL JOINs • CTEs • Window functions Subqueries • Aggregations • Indexes Partitioning • Query optimization 3️⃣ Python Lists • Dicts • Loops • Functions File handling • Exception handling APIs • Pandas • Virtual environments Then pick up 👇 Spark → DBT → Airflow → NoSQL → Cloud → Data Warehouses In 12 years, every strong engineer I met had these 3 locked down first. Don't skip the basics. They show up eventually — in your growth or in your gaps. Follow for more dataengineeringtamil #DataEngineering #DataEngineer #SQL #Python #Linux PySpark Airflow DBT