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Module 1: ETL & ELT (The Water Filtration Plant)

📚 Module 1: ETL & ELT

Course ID: DE-701
Subject: The Filtration Plant

In Data Engineering, our job is to move messy Source A data to clean Destination B.

🏗️ Step 1: ETL (Extract, Transform, Load)

🧩 The Analogy: The Bottled Water Factory

  1. Extract: Pump raw water from a river.
  2. Transform: Filter and bottle it (Clean in memory).
  3. Load: Ship bottles to the store (Warehouse).

🏗️ Step 2: ELT (Extract, Load, Transform)

🧩 The Analogy: The Giant Reservoir

  1. Extract: Pump raw water.
  2. Load: Dump it into a Reservoir (Data Lake).
  3. Transform: Filter it only when someone needs a glass (SQL in Warehouse).

🥅 Module 1 Review

  1. Extract: Getting data.
  2. Transform: Cleaning data.
  3. Load: Saving data.
  4. ELT: The modern way using SQL power.

:::tip Slow Learner Note Even just reading a CSV and cleaning it in Python is a real ETL pipeline! :::