> ## Documentation Index
> Fetch the complete documentation index at: https://private-7c7dfe99-fix-nav-issues.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

> This table contains dimensional metrics that can be calculated instantly and exported in the Prometheus format. It is always up to date.

# system.dimensional_metrics

<Info>
  **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](/reference/system-tables/overview#system-tables-in-clickhouse-cloud) for further details.
</Info>

<h2 id="description">
  Description
</h2>

This table contains dimensional metrics that can be calculated instantly and exported in the Prometheus format. It is always up to date.

<h2 id="columns">
  Columns
</h2>

* `metric` ([String](/reference/data-types/index)) — Metric name.
* `value` ([Float64](/reference/data-types/index)) — Metric value.
* `description` ([String](/reference/data-types/index)) — Metric description.
* `labels` ([Map(String, String)](/reference/data-types/index)) — Metric labels.

<h2 id="example">
  Example
</h2>

You can use a query like this to export all the dimensional metrics in the Prometheus format.

```sql theme={null}
SELECT
  metric AS name,
  toFloat64(value) AS value,
  description AS help,
  labels,
  'gauge' AS type
FROM system.dimensional_metrics
FORMAT Prometheus
```

<h2 id="metric_descriptions">
  Metric descriptions
</h2>

<h3 id="merge_failures">
  merge\_failures
</h3>

Number of all failed merges since startup.

<h3 id="startup_scripts_failure_reason">
  startup\_scripts\_failure\_reason
</h3>

Indicates startup scripts failures by error type. Set to 1 when a startup script fails, labelled with the error name.

<h3 id="merge_tree_parts">
  merge\_tree\_parts
</h3>

Number of merge tree data parts, labelled by part state, part type, and whether it is a projection part.

<h2 id="see-also">
  See also
</h2>

* [system.asynchronous\_metrics](/reference/system-tables/asynchronous_metrics) — Contains periodically calculated metrics.
* [system.events](/reference/system-tables/events) — Contains a number of events that occurred.
* [system.metric\_log](/reference/system-tables/metric_log) — Contains a history of metrics values from tables `system.metrics` and `system.events`.
* [Monitoring](/guides/oss/deployment-and-scaling/monitoring/monitoring) — Base concepts of ClickHouse monitoring.