SQL Fundamentals

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Lab4 objectives100 XP

16.Combine Results

Think before you run it: how many rows does this return? CS-101 is taught in both semesters.

sql

SELECT course_id FROM teaches WHERE semester = 'Fall' AND year = 2025
UNION
SELECT course_id FROM teaches WHERE semester = 'Winter' AND year = 2026;

Run it: the courses taught in Fall 2025 or in Winter 2026, each once.
The same two lists, with every row kept: 10 rows.
Every person in the university: name, then a role column with the text student or instructor. Sort by name.

Something unclear, wrong or missing?

Databaselab-db · PostgreSQL in your browser 0:00

SELECT course_id FROM teaches WHERE semester = 'Fall' AND year = 2025;

Ctrl↵runs the query · select text to run part of it

Objective 1 of 40/4 done

Predict the UNION