ETL Process with MySQL: Extract, Transform, Load

ETL — Extract, Transform, Load — is how raw operational data becomes analysis-ready. MySQL commonly plays both roles: the source you extract from and the target you load into.

Key Points

• Extract: pull increments using timestamps or auto-increment IDs, not full dumps
• Transform: clean, join, and standardise with SQL (staging tables help)
• Load: INSERT … SELECT into final tables; upsert with ON DUPLICATE KEY UPDATE
• Idempotency: re-running a job shouldn't duplicate data
• Log every run: rows in, rows out, duration, errors
• Schedule with cron/Airflow; MySQL events work for simple cases