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CREATE TABLE users (
`user_id` INTEGER,
`name` VARCHAR(7)
);
INSERT INTO users
(`user_id`, `name`)
VALUES
('1', 'Bob'),
('2', 'Adam'),
('3', 'Charlie');
Records: 3 Duplicates: 0 Warnings: 0
SELECT u1.name AS user1,
NULLIF(u2.name, u1.name) AS user2
FROM users u1 CROSS JOIN users u2
ORDER BY u1.user_id, NULLIF(u2.user_id, u1.user_id);
| user1 | user2 |
|---|---|
| Bob | null |
| Bob | Adam |
| Bob | Charlie |
| Adam | null |
| Adam | Bob |
| Adam | Charlie |
| Charlie | null |
| Charlie | Bob |
| Charlie | Adam |