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ClickHouseDatabaseMetaData.getCatalogs exceeds max_execution_time, causing the connection not to be released

Open akenO8 opened this issue 1 year ago • 0 comments

class: ClickHouseDatabaseMetaData.getCatalogs

SELECT
    event_time,
    query_duration_ms,
    initial_user,
    query sql,
    if(exception_code = 0,'success',exception) exception,
    Settings
FROM clusterAllReplicas('ck', 'system.query_log')
WHERE event_time>='2024-02-29 14:39:00'
AND event_time<'2024-02-29 14:40:00'
AND query_duration_ms>600000
ORDER BY event_time DESC limit 10;\G
event_time:        2024-02-29 14:39:11
query_duration_ms: 822838
initial_user: trino
sql:               select name as TABLE_CAT from system.databases order by name settings max_execution_time=20
exception:         success
Settings:          {'max_threads':'6','use_hedged_requests':'0','queue_max_wait_ms':'120000','use_uncompressed_cache':'0','background_fetches_pool_size':'26','background_schedule_pool_size':'256','load_balancing':'random','log_queries':'1','max_concurrent_queries_for_user':'100','send_progress_in_http_headers':'1','join_use_nulls':'1','max_replica_delay_for_distributed_queries':'1','distributed_ddl_task_timeout':'360','max_execution_time':'20','timeout_before_checking_execution_speed':'60','max_memory_usage':'50000000000','max_memory_usage_for_user':'50000000000','enable_global_with_statement':'1','date_time_input_format':'best_effort','insert_distributed_one_random_shard':'1'}

clickhouse-server HTTP connection: image This will cause many queries for that user to fail.

  1. Why does settings max_execution_time=20 in sql not take effect?
  2. show create user trino get max_execution_time = 600, This setting does not take effect either.
  3. How can I avoid time-out metadata queries that on system.databases like this? Can I set it in clickhouse-jdbc?

akenO8 avatar Mar 05 '24 11:03 akenO8