#clikchouse

ClickHouse ORDER BY 排序优化 optimize_read_in_order 参数

起因 排查到线上的一条 SQL 执行的非常慢，SQL 语句如下，其中 prewhere 的限制条件有许多，这里省略了： SELECT UUIDNumToString(info_id) as uid, * FROM people PREWHERE ((location_id = 111 AND capture_time >= 1632312295 AND capture_time <= 1632312415) name in ("zhenng","zheng","zhang") ORDER BY...