CREATE TABLE process_blockers (
    process INTEGER NOT NULL,
    condition INTEGER NOT NULL,
    PRIMARY KEY (process, condition),
    FOREIGN KEY (process) REFERENCES processes(id),
    FOREIGN KEY (condition) REFERENCES conditions(id)
);
CREATE TABLE todo_blockers (
    todo INTEGER NOT NULL,
    condition INTEGER NOT NULL,
    PRIMARY KEY (todo, condition),
    FOREIGN KEY (todo) REFERENCES todos(id),
    FOREIGN KEY (condition) REFERENCES conditions(id)
);
