An OpenAPI query allows you to create queries that call a method in a bespoke assembly to generate data. They allow developers to build their own data sources.  For more details on using this type of query, see How do I create an open API query?

Enter the fully qualified Class Name.If needed you can enter any configuration string required for the Class.

You can choose to summarize the data being returned by selecting the check box.

If you want the Configuration string to have required values then you can use the "Insert Required Values" button to load the Required Value Screen.

Adding two Required fields would create the following

Once you have finished making your selections click on the 'Next >' button

If you are summarizing the data then this will move on to the Query Wizard - Select Columns ( Google Analytics) screen. If required Vales have been added the Run Query Wizard will run to get data to allow the Summarization to be defined.

Otherwise you will move to the Data Definition - Publish Settings screen.