When you modify a data template, you can enhance the data points for your layout by adding a Text object that reveals information about the record returned.
For example, you might want each item in a tree chart to show the name of a department in a store, preceded by the word Department. You could insert a Text object into the data template and then specify a property expression which combines the column name and a literal string.
Value ="Department:"+newline+dept_desc
In this expression, dept_desc is a column returned by the query to your data template.