Querying in ClickHouse CloudThe 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
This table contains dimensional metrics that can be calculated instantly and exported in the Prometheus format. It is always up to date.Columns
metric(String) — Metric name.value(Float64) — Metric value.description(String) — Metric description.labels(Map(String, String)) — Metric labels.
name— Alias formetric.
Example
You can use a query like this to export all the dimensional metrics in the Prometheus format.Metric descriptions
merge_failures
Number of all failed merges since startup.startup_scripts_failure_reason
Indicates startup scripts failures by error type. Set to 1 when a startup script fails, labelled with the error name.merge_tree_parts
Number of merge tree data parts, labelled by part state, part type, and whether it is a projection part.filesystem_cache_evictions_total
Number of file segments evicted from a filesystem cache, labelled by cache name. Disabled by default; enable with expose_prometheus_eviction_metrics.
filesystem_cache_evicted_bytes_total
Total bytes of file segments evicted from a filesystem cache, labelled by cache name. Disabled by default; enable with expose_prometheus_eviction_metrics.
filesystem_cache_evictions_by_user_total
Number of file segments evicted from a filesystem cache, labelled by cache name and user id. Disabled by default; enable with expose_prometheus_eviction_metrics and expose_prometheus_eviction_metrics_per_user.
filesystem_cache_evicted_bytes_by_user_total
Total bytes of file segments evicted from a filesystem cache, labelled by cache name and user id. Disabled by default; enable with expose_prometheus_eviction_metrics and expose_prometheus_eviction_metrics_per_user.
object_storage_queue_failures_total
Number of ObjectStorageQueue (S3Queue/AzureQueue) failures, labelled by database, table, processing stage (read, set_processing, insert, commit) and error code.
object_storage_queue_permanently_failed_files_total
Number of ObjectStorageQueue (S3Queue/AzureQueue) files given up on for good after exhausting retries (or with retries disabled), labelled by database and table. Each of these represents a file whose data will never be processed.
object_storage_queue_newest_seen_object_timestamp_seconds
Unix timestamp of the last-modified time of the newest object seen so far by an ObjectStorageQueue (S3Queue/AzureQueue) table, labelled by database and table.
object_storage_queue_newest_committed_object_timestamp_seconds
Unix timestamp of the last-modified time of the newest object fully processed so far by an ObjectStorageQueue (S3Queue/AzureQueue) table, labelled by database and table.
See also
- system.asynchronous_metrics — Contains periodically calculated metrics.
- system.events — Contains a number of events that occurred.
- system.metric_log — Contains a history of metrics values from tables
system.metricsandsystem.events. - Monitoring — Base concepts of ClickHouse monitoring.