Check if a setting was applied with clickhouse-client - clickhouse

Question

How can I check if a cluster setting is applied on server?
For example,
I run --query "SET allow_experimental_live_view = 1" on my cluster.
Which query should I use to check that this setting was changed? Is it possible to do with clickhouse-client command?
This question is similar but does not answer mine How to check whether Clickhouse server-settings is really applied?

Answer 1

clickhouse-client has many options. Let's check them:
clickhouse-client --help
...
--allow_experimental_live_view arg Enable LIVE VIEW. Not mature enough.
--live_view_heartbeat_interval arg The heartbeat interval in seconds to indicate live query is alive.
--max_live_view_insert_blocks_before_refresh arg Limit maximum number of inserted blocks after which mergeable blocks are dropped and query is re-executed.
...
It needs to pass it this way:
clickhouse-client --allow_experimental_live_view 1
To check the current settings use:
SELECT *
FROM system.settings
WHERE name LIKE '%_live_%'
┌─name───────────────────────────────────────┬─value─┬─changed─┬─description────────────────────────────────────────────────────────────────────────────────────────────────┬─min──┬─max──┬─readonly─┬─type────┐
│ tcp_keep_alive_timeout │ 0 │ 0 │ The time in seconds the connection needs to remain idle before TCP starts sending keepalive probes │ ᴺᵁᴸᴸ │ ᴺᵁᴸᴸ │ 0 │ Seconds │
│ allow_experimental_live_view │ 1 │ 1 │ Enable LIVE VIEW. Not mature enough. │ ᴺᵁᴸᴸ │ ᴺᵁᴸᴸ │ 0 │ Bool │
│ max_live_view_insert_blocks_before_refresh │ 64 │ 0 │ Limit maximum number of inserted blocks after which mergeable blocks are dropped and query is re-executed. │ ᴺᵁᴸᴸ │ ᴺᵁᴸᴸ │ 0 │ UInt64 │
│ temporary_live_view_timeout │ 5 │ 0 │ Timeout after which temporary live view is deleted. │ ᴺᵁᴸᴸ │ ᴺᵁᴸᴸ │ 0 │ Seconds │
│ periodic_live_view_refresh │ 60 │ 0 │ Interval after which periodically refreshed live view is forced to refresh. │ ᴺᵁᴸᴸ │ ᴺᵁᴸᴸ │ 0 │ Seconds │
└────────────────────────────────────────────┴───────┴─────────┴────────────────────────────────────────────────────────────────────────────────────────────────────────────┴──────┴──────┴──────────┴─────────┘
To run this query around all cluster nodes see is there a better way to query system tables across a clickhouse cluster?.