Template variables: dynamically filter dashboards

First, you'll define a template variable. This is the variable that you'll use in a NRQL query to create a widget.

To define a variable:

1. From a new dashboard without variables, click the edit button, and then, click + Add variable button located at the top-left corner. Once you've finished adding variables, click Done editing.

   If the dashboard includes widgets, click the + Add variable button.

   

2. Complete the Add variable workflow. Below are some rules and tips for each of the fields.

   Field	Details
   Name to use in queries	The name of the variable. This is what you'll use in the query, surrounded by {{...}}. For example, if you use country here as the name, then when writing a query you'll call the variable with {{country}}. Variable names must start with a letter and can contain letters, numbers, and underscores.
   Display name	Optional. This is how the variable will display above the dashboard so that dashboard users know what the variable represents. If this is left blank, it will use the main name value.
   Type	There are three options: Query: You can write a query that will return a dynamic list of options used in the dropdown menu. For example, the following query would return a dynamic list of country values: SELECT uniques(countryCode) FROM PageAction since 2 days ago Copy For rules and tips on writing queries, see Query-type variables. List: A list of comma-separated values that are used to populate the options in the dropdown menu. For example, you could manually define a list of country values using a list like: ES, US, CA. Text field: Instead of a dropdown of values to choose from, this allows dashboard users to filter for whatever text they input.
   Account	Only present for query type. For organizations with multiple accounts, this sets the account that is queried.
   Query	Write here your query using uniques (attribute).
   Ignore time picker	Optional. Only present for query type. By turning this option off, the query will be run using the selected time picker’s value in the dashboard. That way, when the value of the time picker changes, the results of the variable’s dropdown will dynamically respond to the new selected time range.
   Multi-select	Optional. This option allows a dropdown to allow multiple selections at the same time instead of a single selection.
   Default values	Optional. These are the defaults value that the dashboard will filter on. For example, if you used the country query above, you could input ES as the default value and the dashboard would automatically filter to that value. You can also select all possibilities. To use multiple values on a WHERE clause you need to use IN instead of =.
   Output format	This lets you change how the data generated by the variable is handled in the query. The selected option you choose here is related to the query you're going to add later in the widget. The default option is string because this is the more common option used in the majority of queries. You can change the default option to one of these: String: Use this for non-numeric text values. Number: Use this for numeric values. Identifier: Use this when you want to substitute parts of the query, like event names or facet names.

   See this example of what a template variable for country values would look like:

   

   Once you've defined your template variable, you can add a widget that uses your created template variable.

Once you've configured a template variable, you'll need widgets on a dashboard that use the variable that you've defined in their query.

To create a widget:

1. From your dashboard click + Add widget button located at the top-right corner.

2. There are 2 options:

   • Add a chart. You'll create your widget using the query builder.
   • Add text, images, or links. You'll create your widget adding your own content using our Markdown editor.

3. We choose Add a chart option.

4. Add your query and click Run.

   Following our example mentioned in step 1:

   SELECT countryCode FROM PageAction WHERE countryCode IN ({{countryCode}})

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   Notice that these are the NRQL clauses that will accept template variables as values: SELECT, FROM, FACET, ORDER BY and WHERE.

   Instead, the following list of NRQL clauses will not accept template variables as arguments: AS, COMPARE WITH, LIMIT, OFFSET, SINCE, SLIDE BY, TIMESERIES, UNTIL and WITH....

5. Click Save

You can enable the multi-value option from the display options section when creating a variable of type NRQL/ENUM.

Here's an example of a query that creates a variable named {{MultiValue}} and returns a list of all unique eventId's:

SELECT uniques(eventId) FROM AjaxRequest

Then you would create a widget with the following query:

SELECT count(*) FROM AjaxRequest WHERE eventId IN ({{MultiValue}})

You can define only one template variable at a time, but you can use more than one template variable in a single widget.

Here's an example of a query that uses two template variables. Note that this assumes the countryCode and city template variables would have already been created and that they have a single value.

SELECT countryCode, city FROM PageAction WHERE countryCode = {{countryCode}} and city = {{city}}

If you have multiple values for your variables, such as Chicago, New York, Paris for your city variable, you need to use IN:

SELECT countryCode, city FROM PageAction WHERE countryCode IN ({{countryCode}}) and city IN ({{city}})

Using variables and regex, you can create a filter, provided you're sure that a part of the filter is fixed.

You need to use this partial match if you want to use like.

Let's say you want to filter by release version. The query returns something like: release-1234.

You can create a variable using aparse to parse the version number:

SELECT uniques(aparse(platformVersion , 'release-*')) FROM PageView

Then create a widget with the following query:

SELECT count(*) FROM PageAction WHERE aparse(platformVersion, 'release-*') IN ({{releaseversion}}) facet platformVersion

Or if you prefer, you could use the capture command:

SELECT count(*) FROM PageAction WHERE capture(platformVersion, r'release-(?P<platformVersion>\d+)') IN ({{releaseversion}}) Facet platformVersion

You can use LIKE and RLIKE as template variables to filter data in a dashboard. To use this feature, the value you add when creating the template variable must use the % wildcard symbols at the start and end of the value.

Here's an example. You define a string variable, as shown here:

You can then create a widget chart and use your variable like this:

FROM NrdbQuery SELECT user WHERE user LIKE {{like_filter}}

or like this:

FROM NrdbQuery SELECT user WHERE user RLIKE {{like_filter}}

You can create a variable of type NRQL with a string output format and use it after a facet clause to group by different values.

For example, you might create a variable named {{userAgentName}} that would look like:

SELECT uniques(userAgentName) FROM PageAction

Then you'd create a widget with the following query:

SELECT count(*) FROM PageAction WHERE userAgentName={{userAgentName}} FACET userAgentName

You can create a variable with an identifier output format and use it after a FACET clause to group by different values.

For example, you might create a {{location}} variable of type list with two possible values: countryCode and city. You'd set the output format to identifier.

Then you'd create a widget with the following query:

SELECT count(*) FROM PageAction FACET {{location}}

You can create a variable with output format number and use that inside a percentile function.

For example, you could create a {{percentile}} variable of type list with two possible values: 55 and 90. You'd want to set the output format as number.

Then you'd create a widget with the following query:

SELECT percentile(duration,{{percentile}}) FROM PageAction

To use variables for filtering you only need to add the created variable on the right side of a WHERE clause, like this:

SELECT countryCode, city FROM PageAction WHERE countryCode IN ({{countryCode}})

By default the “ignore time picker” option is enabled, meaning that the query is always run using the default 1 HOUR time range value, even if the time picker in the dashboard has a different value selected (ex. 5 minutes, 3 hours, etc). The exception for that case is when the query has an explicit time range set with a SINCE clause, like for example:

SELECT uniques(eventId) 
FROM AjaxRequest 
SINCE 5 minutes ago

The results will be in the range of the last 5 minutes.

When the “ignore time picker” option is turned off, the query will run with the value selected in the time picker. For example, if you set the time picker to 30 minutes, such as in the screenshot below, in the form for editing the variables, the "ignore time picker" field will set to off.

This results in the values for the last 30 minutes. When you set the time picker value to Default and your query has a SINCE clause, the latest value will be used to run the query.

Sometimes you have queries that apply the same rules to different types of data. Here are examples of two widgets that are identical except for the data type:

• Widget 1:

  SELECT count(*) FROM DataType1 SINCE 1 day ago

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• Widget 2:

  SELECT count(*) FROM DataType2 SINCE 1 day ago

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  Instead of creating two separate widgets, you can create one widget with a variable that has the Identifier for Output format. Then, you can use it in a FROM clause to query different data types.

  For example, you might create a {{dataType}} variable of type List with two possible values: DataType1 and DataType2. You'd set the Output Format to Identifier:

  

  Then, you'd create and run the widget: