If you want to change the position of the fields you added to a data source, Microsoft InfoPath Team Blog: Moving fields in the data source shows you how to move those fields by using the mouse or the keyboard.
The techniques in this blog post apply only to fields that you have added to a data source. You cannot move the fields in a data source that is based on an external data source, such as a database or a Web Service. The external data source determines the position of the fields in the data source of the form template, and the order of those fields cannot be changed in InfoPath.
For more information about fields and data sources, see the following articles:
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