← Data Analysis with SQL

Lesson 3 of 3 · 12 min

Joining tables

JOIN combines tables on a shared column: orders JOIN customers ON orders.customer_id = customers.id.

INNER JOIN keeps only matches; LEFT JOIN keeps all rows from the left table.

Practice

Sketch two tables (students, courses) and write the JOIN that lists each student with their course.

Quiz

+50 pts
1. JOINs connect tables on…
2. LEFT JOIN keeps…

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