system.histogram_metric_log

Querying in ClickHouse Cloud

The data in this system table is held locally on each node in ClickHouse Cloud. Obtaining a complete view of all data, therefore, requires the clusterAllReplicas function. See here for further details.

Description

History of system.histogram_metrics. Snapshot taken every collect_interval_milliseconds, flushed to disk.

Columns

• hostname (LowCardinality(String)) — Hostname of the server executing the query.
• event_date (Date) — Event date.
• event_time (DateTime) — Event time.
• event_time_microseconds (DateTime64(6)) — Event time with microseconds resolution.
• metric (LowCardinality(String)) — Metric name.
• labels (Map(LowCardinality(String), LowCardinality(String))) — Metric labels.
• histogram (Map(Float64, UInt64)) — Cumulative histogram: maps bucket upper bound to number of observations ≤ that bound; includes +inf as the final bucket.
• count (UInt64) — Total number of observations, equals histogram[+inf].
• sum (Float64) — Sum of all observed values.

Example

SELECT event_time, metric, labels, histogram
FROM system.histogram_metric_log
WHERE metric = 'keeper_response_time_ms'
ORDER BY event_time DESC
LIMIT 1
FORMAT Vertical;

See Also

• system.histogram_metrics — Live histogram metrics.
• system.metric_log — History of system.metrics and system.events.