The data sources id is a unique string used to reference a data source in your custom JavaScript. For example, you can use the following JavaScript to return all the rows in a specific data source.
tf.getDataSource('insertDataSourceId')
You can use the following steps get the id of your data source:
Navigate to the data sources screen by clicking the "..." on the form builder screen or via the context menu for a team in the side bar
Locate the data source you wish to reference and click the "..." icon followed by "Data Source Id"
The Id will be listed at the top of the popup menu that will appear
