> NOTE: If you're not seeing the `Data Sources` link in your side menu it means that your current user does not have the `Admin` role for the current organization.
*Query expression* | Prometheus query expression, check out the [Prometheus documentation](http://prometheus.io/docs/querying/basics/).
*Legend format* | Controls the name of the time series, using name or pattern. For example `{{hostname}}` will be replaced with label value for the label `hostname`.
*Min step* | Set a lower limit for the Prometheus step option. Step controls how big the jumps are when the Prometheus query engine performs range queries. Sadly there is no official prometheus documentation to link to for this very important option.
*Resolution* | Controls the step option. Small steps create high-resolution graphs but can be slow over larger time ranges, lowering the resolution can speed things up. `1/2` will try to set step option to generate 1 data point for every other pixel. A value of `1/10` will try to set step option so there is a data point every 10 pixels.
*Metric lookup* | Search for metric names in this input field.
*Format as* | Switch between Table, Time series or Heatmap. Table format will only work in the Table panel. Heatmap format is suitable for displaying metrics having histogram type on Heatmap panel. Under the hood, it converts cumulative histogram to regular and sorts series by the bucket bound.
For details of *metric names*, *label names* and *label values* are please refer to the [Prometheus documentation](http://prometheus.io/docs/concepts/data_model/#metric-names-and-labels).
It's possible to use some global built-in variables in query variables; `$__interval`, `$__interval_ms`, `$__range`, `$__range_s` and `$__range_ms`, see [Global built-in variables](/reference/templating/#global-built-in-variables) for more information. These can be convenient to use in conjunction with the `query_result` function when you need to filter variable queries since
Make sure to set the variable's `refresh` trigger to be `On Time Range Change` to get the correct instances when changing the time range on the dashboard.
**Example usage:**
Populate a variable with the the busiest 5 request instances based on average QPS over the time range shown in the dashboard:
```
Query: query_result(topk(5, sum(rate(http_requests_total[$__range])) by (instance)))
Why two ways? The first syntax is easier to read and write but does not allow you to use a variable in the middle of a word. When the *Multi-value* or *Include all value*
options are enabled, Grafana converts the labels from plain text to a regex compatible string. Which means you have to use `=~` instead of `=`.
- A Prometheus query for pending and firing alerts (for details see [Inspecting alerts during runtime](https://prometheus.io/docs/prometheus/latest/configuration/alerting_rules/#inspecting-alerts-during-runtime))
Since 4.6.0 Grafana exposes metrics for Prometheus on the `/metrics` endpoint. We also bundle a dashboard within Grafana so you can get started viewing your metrics faster. You can import the bundled dashboard by going to the data source edit page and click the dashboard tab. There you can find a dashboard for Grafana and one for Prometheus. Import and start viewing all the metrics!
It's now possible to configure datasources using config files with Grafana's provisioning system. You can read more about how it works and all the settings you can set for datasources on the [provisioning docs page](/administration/provisioning/#datasources)
