DROP TABLE IF EXISTS alter_00665; CREATE TABLE alter_00665 (`boolean_false` Nullable(String)) ENGINE = MergeTree ORDER BY tuple(); INSERT INTO alter_00665 (`boolean_false`) VALUES (NULL), (''), ('123'); SELECT * FROM alter_00665; SELECT * FROM alter_00665 ORDER BY boolean_false NULLS LAST; ALTER TABLE alter_00665 MODIFY COLUMN `boolean_false` Nullable(UInt8); SELECT * FROM alter_00665; SELECT * FROM alter_00665 ORDER BY boolean_false NULLS LAST; DROP TABLE alter_00665;