How ClickHouse handles strings

At my work, we use ClickHouse to process billions of records and hundreds of terabytes of data. ClickHouse is fast, and its speed got me curious to learn some of its internals. Let's look at a few queries: SELECT count ( * ) FROM cluster . feed WHERE state = 'unknown' ┌────── count () ─┐ 1 . │ 129375618342 │ -- 129.38 billion [......]