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AI ENGINEER FOUNDATIONS · STAGE 02

Data handling & engineering foundations

Move data safely and make it useful.

Learning objective

Learn how structured data moves from its source to reliable analytical tables. Focus on formats, SQL, transformations, data quality, and repeatable pipelines.

BEFORE YOU START

Prerequisites

  • Basic programming and data structures

LEARNING OBJECTIVES

What you should be able to do

  • Read common structured data formats
  • Explain ETL and ELT
  • Design a pipeline with validation and safe retries

WHAT YOU'LL COVER

Key concepts

01Data formats
02SQL fundamentals
03Data pipelines
04ETL and ELT
05Data quality and reliability

SEE THE CONNECTIONS

A visual learning sequence

Data handling & engineering foundations: a useful way to approach the work
01Inspect the dataUnderstand schema, formats, ownership, and update frequency.
02Transform deliberatelyUse SQL and code to clean and model records.
03Make it reliableAdd validation, idempotency, orchestration, and monitoring.

These are connected learning steps, not the only valid order. Revisit earlier ideas when an exercise reveals a gap.

Suggested learning sequence

01

Inspect the data

Understand schema, formats, ownership, and update frequency.

Why it matters: Unclear inputs create downstream assumptions and failures.

02

Transform deliberately

Use SQL and code to clean and model records.

Why it matters: Consumers need stable and understandable datasets.

03

Make it reliable

Add validation, idempotency, orchestration, and monitoring.

Why it matters: Pipelines need to recover from real operational failures.

Put it into practice

Create an orders pipeline that validates required fields, deduplicates by order ID, and safely merges late updates.

Practice tasks

  • Draw an ETL and ELT flow for a warehouse.
  • Define freshness and uniqueness checks for a dataset.
  • Explain how a retry avoids duplicate output.

How you'll know you're ready

  • Can describe where transformation happens in ETL versus ELT.
  • Can name reliability controls beyond simply retrying.

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