18.Both or Only One

The id of each student who takes a course in Fall 2025 and a course in Winter 2026.
The id of each student who takes a course in Fall 2025 but none in Winter 2026.
The course_id of each course that is not a prerequisite of any course (see the prereq tab).
Which course do students take that nobody teaches? Give its course_id.

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Databaselab-db · PostgreSQL in your browser 0:00

SELECT id FROM takes WHERE semester = 'Fall' AND year = 2025;

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Objective 1 of 40/4 done