clickhouse 自用语句记录
聚合查询：
SELECT
toStartOfInterval(CREATE_TIME, INTERVAL 60 SECOND) AS interval_start,
ROUND(AVG(CPU_USED), 1) AS avg_cpu_used,
ROUND(AVG(MEMORY_USED), 1) AS avg_memory_used,
ROUND(AVG(DISK_USED), 1) AS avg_disk_used
FROM MWLOGDB_ANALYSIS.SYSTEM_MONITOR
GROUP BY interval_start
ORDER BY interval_start;
此语句的作用为：以60s聚合数据，并且只保留小数点后一位值