Context: CREATE TABLE Courses (subject_id VARCHAR); CREATE TABLE Subjects (subject_name VARCHAR, subject_id VARCHAR)
Question: Find the subject ID, subject name, and the corresponding number of available courses for each subject.
Answer: SELECT T1.subject_id, T2.subject_name, COUNT(*) FROM Courses AS T1 JOIN Subjects AS T2 ON T1.subject_id = T2.subject_id GROUP BY T1.subject_id