-- Default CEFR-style courses per seeded program: Beginner→A1,A2; Intermediate→B1,B2; Advanced→C1,C2.
-- Custom courses can still be created via the API with any name.
INSERT INTO courses (program_id, name, description, thumbnail)
SELECT
    p.id,
    v.name,
    'Default CEFR level course (system seed).',
    NULL
FROM programs AS p
INNER JOIN (
    VALUES
        ('Beginner', 'A1'),
        ('Beginner', 'A2'),
        ('Intermediate', 'B1'),
        ('Intermediate', 'B2'),
        ('Advanced', 'C1'),
        ('Advanced', 'C2')
) AS v (program_name, name)
    ON p.name = v.program_name;