CREATE TABLE students (
    student_id STRING,
    name STRING,
    birthyear INTEGER,
    gender STRING
);

CREATE TABLE classes (
    class_id STRING,
    name STRING
);

CREATE TABLE grades (
    student_id STRING,
    class_id STRING,
    points FLOAT
);

INSERT INTO students VALUES ('1', 'Kadjo', 1979, 'M');
INSERT INTO students VALUES ('2', 'Baird', 1981, 'M');
INSERT INTO students VALUES ('3', 'Goober', 1800, 'M');
INSERT INTO classes VALUES ('ECON490', 'IT Economics');
INSERT INTO classes VALUES ('EE231', 'Digital Electronics');
INSERT INTO grades VALUES ('1', 'ECON490', 1.0);
INSERT INTO grades VALUES ('2', 'ECON490', 2.0);
INSERT INTO grades VALUES ('2', 'EE231', 3.0);
INSERT INTO grades VALUES ('3', 'EE231', 4.0);

.mode list
.separator ' '

SELECT c.name, SUM(g.points)/COUNT(g.points)
    FROM grades AS g,
         classes AS c
    WHERE g.class_id = c.class_id
    GROUP BY c.class_id;

SELECT s.name, SUM(g.points)/COUNT(g.points)
    FROM grades AS g,
         students AS s
    WHERE g.student_id = s.student_id
    GROUP BY s.student_id;