drop table if exists default.test_qualify; create table default.test_qualify (number Int64) ENGINE = MergeTree ORDER BY (number); insert into default.test_qualify SELECT * FROM numbers(100); select count() from default.test_qualify; -- 100 select * from default.test_qualify qualify row_number() over (order by number) = 50 SETTINGS allow_experimental_analyzer = 1; -- 49 select * from default.test_qualify qualify row_number() over (order by number) = 50 SETTINGS allow_experimental_analyzer = 0; -- { serverError NOT_IMPLEMENTED } delete from default.test_qualify where number in (select number from default.test_qualify qualify row_number() over (order by number) = 50); -- { serverError UNFINISHED } select count() from default.test_qualify; -- 100