SQLite 3.27

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PRAGMA foreign_keys = ON;
CREATE TABLE Links (
    link_id INTEGER PRIMARY KEY,
    link_description TEXT
);
INSERT INTO Links(link_id, link_description) VALUES
    (1, 'link1'), (2, 'link2'), (3, 'link3');

3 rows affected


CREATE TABLE Parts (
    part_id INTEGER PRIMARY KEY,
    part_description TEXT
);
INSERT INTO Parts(part_id, part_description) VALUES
    (1, 'part1'), (2, 'part2'), (3, 'part3');

3 rows affected


CREATE TABLE Links_Parts (
    link_id INTEGER NOT NULL REFERENCES Links(link_id),
    part_id INTEGER NOT NULL REFERENCES Parts(part_id),
    PRIMARY KEY(link_id, part_id)
);
INSERT INTO Links_Parts(link_id, part_id) VALUES
    (1, 1), (1, 3), (2, 3), (3, 1);

4 rows affected


CREATE TABLE Main (
    main_id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
    link_id INTEGER NOT NULL REFERENCES Links(link_id)
);
INSERT INTO Main(main_id, link_id) VALUES
    (1, 1), (2, 1), (3, 2); 

3 rows affected