MySQL 8.0

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CREATE TABLE User (
    id INT,
    status varchar(15),
    postId int 
);

INSERT INTO User VALUES
(12345,'new',55555),
(23456,'ready',55555),
(34567,'done',77777);
select * from User;


id
status
postId


12345
new
55555

23456
ready
55555

34567
done
77777


select postId
from User
where status in ('new','ready')
group by postId
having count(distinct status) >=2;


postId


55555