Count rows safely with LEFT JOIN

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`LEFT JOIN` keeps every row of the left table even when nothing matches, and `COUNT(column)` ignores NULLs — the safe way to count related rows.

Task: Count rows safely with LEFT JOIN. Which rows come back?

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What you start with

SELECT c.title, COUNT(s.id) AS enrolled
FROM courses c
LEFT JOIN students s ON s.course_id = c.id
GROUP BY c.id
ORDER BY enrolled DESC, c.title;

SQL 1 automatic check Capstone: reports a client would pay for

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SELECT c.title, COUNT(s.id) AS enrolled
FROM courses c
LEFT JOIN students s ON s.course_id = c.id
GROUP BY c.id
ORDER BY enrolled DESC, c.title;

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