Normally in design more a text shape is always displaying the linked value returned from the external data source. But it can be interesting to display some additional information during the design for reviewing.

You can display the row number, column name, connection name etc by choosing an option from the DataPoint > Display menu.

In design mode the content of the dynamic shapes are set when you open your presentation or when you change a property of a PowerPoint shape. During the design of the presentation, the dynamic content of the shapes will not be refreshed automatically. This is done to maximize your speed and convenience during the design. The dynamic information will only be refreshed when you run the slide show.

In case you do want to refresh the dynamic content, just click DataPoint > Refresh data now.