All About SharePoint is a blog about SharePoint, InfoPath and related technologies. It was started in 2005 and has good readership in many countries. It covers SharePoint 2003, 2007, 2010, 2013, 2016 and Office 365. You can read articles, tips, tutorials and news. It has code samples and complete applications as well.
This article shows how one can populate InfoPath drop downs with "FILTERED" SharePoint list data. This article uses SPQuery to query the SharePoint lists.