Most of the time databases include both types of sources, but you may encounter a strictly scholarly database. Read the database description. Articles are fairly short, providing an overview on a focused topic. Long, in-depth analysis of topics, sometimes very narrowly focused. Reports on original research.
Language can be full of technical jargon.
Written for researchers, professors or students in a particular field. Often glossy paper, lots of pictures, sidebars. Articles do not follow a specific format. Plain paper, sometimes figures, charts and tables included. Author is usually a staff writer or reporter.