renaming column in ClickHouse

If your CH server supports ALTER TABLE UPDATE(if no, sorry but it's time to migrate to new version)  here is trick:

!Before doing it please test on your test data!

create new column

ALTER TABLE my_super_table
    ADD COLUMN
    new_name UInt32 DEFAULT CAST(0, 'UInt32');

later set value

ALTER TABLE my_super_table
    UPDATE new_name = old_name WHERE 1;

Not sure but I think it's better to wait until you merges are finished

drop column

ALTER TABLE my_super_table
    DROP COLUMN old_name;



That's it!