* Changes. to metadata in Manage users * changes to install section * Added titile * More changes. * Updated administration folder metadata, moved 2 files from installation folder. * Added links to Administration landing page, other metadata changes worked out. * Updated alerting section metadata. * Updated metadata of Auth section. Broke index and created separate Grafana Authentication section. * Added correct weight. * Updated metadata for the Best practices section. * Updated metadata in templates, broke Overview topic. * Updated subment Variable types metadata * Fixed yaml file and H1 description of Variables syntax topic. * Couple more metadata changes. * Added aliases files, as suggested by Diana.
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+++ title = "Variables syntax and types" keywords = ["grafana", "templating", "documentation", "guide", "template", "variable"] type = "docs" aliases = ["/docs/grafana/latest/reference/templating"] [menu.docs] identifier = "variables-syntax-types" parent = "variables" weight = 100 +++
Variable syntax
Panel titles and metric queries can refer to variables using two different syntaxes:
$varname
This syntax is easy to read, but it does not allow you to use a variable in the middle of a word. Example: apps.frontend.$server.requests.count${var_name}
Use this syntax when you want to interpolate a variable in the middle of an expression.${var_name:<format>}
This format gives you more control over how Grafana interpolates values. Refer to [Advanced variable format options]({{< relref "advanced-variable-format-options.md" >}}) for more detail on all the formatting types.[[varname]]
Do not use. Deprecated old syntax, will be removed in a future release.
Before queries are sent to your data source the query is interpolated, meaning the variable is replaced with its current value. During interpolation, the variable value might be escaped in order to conform to the syntax of the query language and where it is used. For example, a variable used in a regex expression in an InfluxDB or Prometheus query will be regex escaped. Read the data source specific documentation topic for details on value escaping during interpolation.
For advanced syntax to override data source default formatting, refer to [Advanced variable format options]({{< relref "advanced-variable-format-options.md" >}}).