create table orders (
offerId varchar(2),
users varchar(2),
create_date date,
finish_date date,
Mark varchar(2)
);
insert into orders (offerId, users, create_date, finish_date,Mark)
values
('1a', 'u1', '2020-01-01', '2020-01-02', 'M1'),
('2b', 'u1', '2020-01-03', '2020-01-04', 'M2'),
('3x', 'u1', '2020-01-05', '2020-01-07', 'M1'),
('12', 'u1', '2020-03-04', '2020-03-08', 'M4'),
('4y', 'u1', '2020-03-01', '2020-03-10', 'M4'),
('5z', 'u2', '2020-04-01', '2020-04-05', 'M1'),
('6f', 'u2', '2020-04-06', '2020-04-07', 'M2'),
('7f', 'u2', '2020-04-10', '2020-04-11', 'M4'),
('8f', 'u2', '2020-07-01', '2020-07-09', 'M2'),
('9', 'u3', '2020-08-01', '2020-08-10', 'M2'),
('10', 'u3', '2020-08-03', '2020-08-10', 'M3'),
('11', 'u3', '2020-08-03', '2020-08-10', 'M4');
SELECT DISTINCT users
FROM orders
WHERE not EXISTS (
SELECT DISTINCT Mark
FROM orders
WHERE users = 'u2')
AND users <> 'u2';
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