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CREATE TABLE tablename (`project_id` INTEGER, `user_id` INTEGER, `can_read_by` TEXT);
INSERT INTO tablename (`project_id`, `user_id`, `can_read_by`) VALUES
('1', '7', '2,3,4'),
('2', '6', '3'),
('3', '2', '5'),
('4', '1', '2'),
('5', '5', '3,1');
SELECT *
FROM tablename
WHERE user_id = '2'
OR ',' || can_read_by || ',' LIKE '%,' || '2' || ',%';
| project_id | user_id | can_read_by |
|---|---|---|
| 1 | 7 | 2,3,4 |
| 3 | 2 | 5 |
| 4 | 1 | 2 |