DROP TABLE IF EXISTS test.mergetree; CREATE TABLE test.mergetree (x UInt64) ENGINE = MergeTree ORDER BY x; INSERT INTO test.mergetree VALUES (1); SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM test.mergetree WHERE x IN (SELECT * FROM numbers(10000000)))))))))))); SET force_primary_key = 1; SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM (SELECT * FROM test.mergetree WHERE x IN (SELECT * FROM numbers(10000000)))))))))))); DROP TABLE test.mergetree;