When you are connected to an external data source, you can also perform a refresh operation to retrieve the updated data. The external data source is connected to the workbook through a data connection, which is a set of information that describes how to locate, log in, query, and access the external data source.
The data may be stored directly in the workbook, or it may be stored in an external data source, such as a text file, a database, or an Online Analytical Processing (OLAP) cube. Data in an Excel workbook can come from two different locations.
