@ -39,6 +39,5 @@ Query expressions are different for each data source. For more information, refe
1. (optional) In the **Regex** field, type a regex expression to filter or capture specific parts of the names returned by your data source query. To see examples, refer to [Filter variables with regex]({{< relref "../filter-variables-with-regex.md" >}}).
1. In the **Sort** list, select the sort order for values to be displayed in the dropdown list. The default option, **Disabled**, means that the order of options returned by your data source query will be used.
1. (optional) Enter [Selection Options]({{< relref "../variable-selection-options.md" >}}).
1. (optional) Enter [Value groups/tags]({{< relref "../variable-value-tags.md" >}}).
1. In **Preview of values**, Grafana displays a list of the current variable values. Review them to ensure they match what you expect.
1. Click **Add** to add the variable to the dashboard.
> **Note:** This is an experimental feature that will be deprecated in Grafana v8.
Value groups/tags are a feature you can use to organize variable options. If you have many options in the dropdown for a multi-value variable, then you can use this feature to group the values into selectable tags.
This feature is off by default. Click **Enabled** to turn the feature on.
To see an example, check out [Templating value groups](https://play.grafana.org/d/000000024/templating-value-groups?orgId=1).
## Tags query
Enter a data source query that should return a list of tags. The tags query returns a list of tags that each represents a group, and the tag values query returns a list of group members.
For example, the tags query could be a list of regions (Europe, Asia, Americas), and then if the user selects the Europe tag, then the tag values query would return a list of countries -- Sweden, Germany, France, and so on.
If you have a variable with a lot of values (say all the countries in the world), then this allows you to easily select a group of them. If the user selects the tag Europe, all the countries in Europe would be selected.
In this [example dashboard](https://play.grafana.org/d/ZUPhFVGGk/graphite-with-experimental-tags?orgId=1), the server variable has tags enabled.
## Tag values query
Enter a data source query that should return a list of values for a specified tag key. Use `$tag` in the query to refer to the currently selected tag.
The `$tag` variable will have the value of the tag that the user chooses.
For example, if you have a Graphite query for tags, `regions.*`, that returns a list of regions. The values query could be `regions.$tag.*`, which if the user chooses Europe would be interpolated to `regions.Europe.*`.
// @ts-ignore strict null error TS2345: Argument of type '() => Promise<{ value: string; text: string; }[]>' is not assignable to parameter of type '() => Promise<never[]>'
Hugo Häggmark
5 years ago
committed by