When you create a dashboard with Dashboard Builder, you will frequently need to pass context information that identifies a DataView item to display or operate on. Consider, for example, a dashboard with a table containing one row for each instance of a given instance. In order to display detailed information about an instance when the end user selects its corresponding row in the table, you need to pass the identity of the selected instance to the visualization objects that will display the details.

You can pass such information from one object to another by doing both the following:

In many cases you can simplify this procedure by using the predefined substitution variable $instanceId. This variable is automatically set to the value of apama.instanceId for the table row that is currently selected. If multiple rows are selected, $instanceId is set to multiple values.

For more information and examples, see Performing drilldowns on tables and Specifying drill-down column substitutions.

You will find yourself using $instanceId frequently in attachment filters and instance operations. You will see many uses of $instanceId in subsequent sections of this guide.