水星的随笔

背景

ClickHouse运行一段时间后，发现system库占用空间40G！需要清理。

清理方法

删除对应的分区

ALTER table `system`.asynchronous_metric_log  DELETE where event_date is not null;
ALTER table `system`.metric_log DELETE where event_date is not null;
ALTER table `system`.part_log DELETE where event_date is not null;
ALTER table `system`.query_log DELETE where event_date is not null;
ALTER table `system`.query_thread_log DELETE where event_date is not null;
ALTER table `system`.session_log DELETE where event_date is not null;
ALTER table `system`.trace_log DELETE where event_date is not null;

参考

1. ClickHouse默认库system日志清理方法（query_log、asynchronous_metric_log）
2. Clickhouse清理大日志表