Let's Data ScienceLEARN • BUILD • STAY AHEAD

SQL Mastery

Free

CASE logic, data transformation, subqueries & CTEs, and window functions — the advanced SQL working analysts use every day.

4 modules · Free with a (free) account.

View the full course

What this course covers

A module-by-module concept outline. Open the course to learn each topic with animated explanations, in-browser code, practice challenges, and a knowledge check.

Module 1. Conditional Logic & NULL Handling

Topics

CASE WHEN - SQL's If-Then-ElseCASE for Conditional AggregationCOALESCE - Your NULL Safety NetNULLIF - Preventing ErrorsNULL in Aggregations & Comparisons

Sections

1CASE WHEN - SQL's If-Then-Else
2CASE for Conditional Aggregation
3COALESCE - Your NULL Safety Net
4NULLIF - Preventing Errors
5NULL in Aggregations & Comparisons

Module 2. Data Transformation Functions

Topics

String Functions - Text ManipulationDate & Time FunctionsNumeric FunctionsType Conversion with CAST

Sections

1String Functions - Text Manipulation
2Date & Time Functions
3Numeric Functions
4Type Conversion with CAST

Module 3. Subqueries & CTEs

Topics

Subqueries in WHERECorrelated SubqueriesEXISTS & NOT EXISTSSubqueries in SELECT & FROMCommon Table Expressions (CTEs)

Sections

1Subqueries - Queries Within Queries
2Common Table Expressions (CTEs)
3Subquery vs CTE vs JOIN

Module 4. Window Functions

Topics

Introduction to Window FunctionsRanking Functions: ROW_NUMBER, RANK, DENSE_RANKPARTITION BY - Windows Within WindowsAggregate Window FunctionsFrame Specifications

Sections

1Window Functions - The Big Picture
2Ranking Functions Deep Dive
3Aggregate Window Functions & LAG/LEAD
4Frame Specifications

Ready to start SQL Mastery?

Free with a (free) account — sign in and start learning.

Go to the course

All course syllabi

SQL Fundamentals SQL Window Functions Python Fundamentals Pandas Fundamentals Statistics for Data Science Probability for Data Scientists Machine Learning Fundamentals (scikit-learn)A/B Testing & Experimentation LLM Foundations