ByConity常用SQL语句详解

-- 查询merger任务状态 
SELECT * FROM system.manipulations; 
-- 调整表 Merger 任务 
alter table log.ck_logs_box_10 modify setting cnch_merge_pick_worker_algo='RoundRobin'; 
-- 查看后台累计任务 
SELECT * FROM system.bg_threads 
WHERE database = 'log' AND table = 'web_tools'; 
-- 查看当前 Merger 情况 
select * from system.manipulations; 
-- 查看当前 Merge 并发任务量
SELECT type, database,table, related_node, count(1) 
FROM system.manipulations 
group by type, database,table,related_node;

-- 设置 查询时最大执行时间（单位：s）： settings max_execution_time = 300; 
select ck_date, kind, count() 
from log.ck_logs_box_10 group by ck_date, kind 
settings max_execution_time = 300;

-- 调整表为不使用缓存 enable_local_disk_cache = 0, 用缓存的话 设置为 1 
alter table log.ck_logs_box_10 modify setting enable_local_disk_cache = 0; 
-- 配置为 reard 端主动读取数据 enable_preload_parts = 1，不使用设置为 0
alter table log.ck_logs_box_10 modify setting enable_preload_parts = 0;

-- 删除分区数据  
ALTER TABLE log.ck_logs_box_10 DROP PARTITION '20230706'

-- 查看 parts 
select partition_id, part_type, count(), formatReadableSize(sum(bytes_on_disk)) 
FROM system.cnch_parts 
where database='log' and table='ck_logs_box_10' and part_type='VisiblePart' 
group by partition_id, part_type order by partition_id; 
-- 查看 指定日期的 parts 
select name, rows_count, marks_count, formatReadableSize(bytes_on_disk) 
FROM system.cnch_parts 
where database='log' and table='ck_logs_box_10' and part_type='VisiblePart' and partition_id = '20230719' 
order by bytes_on_disk desc ;

-- 查看Kafka 消费日志， 有错误时，也可以在这里看到
SELECT event_type, event_time, consumer, formatReadableSize(bytes), has_error, exception
FROM cnch_system.cnch_kafka_log
WHERE event_date = today()
 AND cnch_database = 'kafka_consume'
 AND cnch_table =  'ck_logs_box_10'
 AND event_time > now() - 600
ORDER BY event_time desc;
-- 查看 消费情况
SELECT * FROM system.cnch_kafka_tables
WHERE database = 'kafka_consume'
limit 10;
-- 将kafka 引擎停止
SYSTEM STOP CONSUME kafka_consume.ck_logs_box_10;
-- 将kafka 引擎开始
SYSTEM START CONSUME kafka_consume.ck_logs_box_10;
-- 将kafka 引擎重启
SYSTEM RESTART CONSUME kafka_consume.ck_logs_box_10;