create table T (
id_user int,
year int
);
-- insert into T values (1, 2022), (1, 2023), (2, 2023);
insert into T values (1, 2022);
insert into T values (1, 2023);
insert into T values (2, 2023);
select distinct t.id_user from T as t
where
t.year = 2023 and
not exists (select id_user from T tt where year = 2022 and tt.id_user = t.id_user);
select distinct t.id_user
from T as t
left join T tt on tt.year = 2022 and tt.id_user = t.id_user
where t.year = 2023 and tt.id_user is null;
select distinct t.id_user from T as t
where t.year = 2023
except
select distinct t.id_user from T as t
where t.year = 2022
;