Joins in Databases

Description

Joins are how relational databases combine data from separate tables, and this course explains each type with examples. It starts with database relationships and why joins matter, then covers INNER JOIN, LEFT and RIGHT JOIN, FULL OUTER JOIN and CROSS JOIN.

Later lessons cover self-joins for hierarchical data, combining multiple tables, set operations such as UNION, INTERSECT and EXCEPT, and subqueries. The final lessons address performance, e-commerce and analytics case studies, common pitfalls, advanced join patterns and a closing project. Exercises appear in most lessons. Tables in the PDFs summarize the main points of each join type.

Who it is for: learners who know basic SQL and want to combine data from several tables.

What’s included
14 PDF lessons · 102 pages · about 28,500 words
One ZIP download that is yours to keep — read on any device, no subscription or app needed.

Course programme

1. Understanding Database Relationships and Why Joins Matter
2. Getting Started with INNER JOIN: The Most Common Join
3. Mastering LEFT JOIN and RIGHT JOIN for Complete Data Views
4. Working with FULL OUTER JOIN for Comprehensive Data Analysis
5. Exploring CROSS JOIN for All Possible Combinations
6. Practical Self-Joins for Hierarchical Data Structures
7. Combining Multiple Tables with Advanced Join Techniques
8. Set Operations: UNION, INTERSECT, and EXCEPT
9. Subqueries and Their Role in Complex Join Scenarios
10. Performance Optimization and Best Practices for Joins
11. Real-World Case Studies: E-Commerce and Analytics Examples
12. Common Pitfalls and How to Avoid Them
13. Advanced Join Patterns for Complex Business Logic
14. Putting It All Together: Final Project and Review