Find the most popular course

Warm-up · aggregation, joins, filtering

Given 3 tables, students(id, name), courses(id, name), grades(id, course_id, student_id, grade),

find the name of the most popular course: the one with the most enrolled students who are

passing, i.e. scored a grade of at least 50. If there is a tie, return the course name that is

lexicographically smaller. Output the column (name).

Expected columns

name

Hint 1 — filter, then count

Keep only grades >= 50 in WHERE, then GROUP BY the course and COUNT(*) the passing students per course.

Hint 2 — the students table

Each grades row already is one enrolled student. Joining students adds a lookup per row without changing any count.